SMTP和HTTP协议一样都属于请求应答式协议

著论准过秦,作赋拟子虚。这篇文章主要讲述SMTP和HTTP协议一样都属于请求应答式协议相关的知识,希望能为你提供帮助。
电子邮件协议中POP3协议用于接收邮件,SMTP协议用于发送邮件。SMTP的全称为Simple Mail Transfer Protocol,也就是简单邮件传输协议,字如其名。



相较于POP3而言,SMTP确实比较简单。这里的简单并不是指SMTP的命令比POP3少,而是指SMTP的命令是有序的,而POP3的命令是无序的,理解这一点很重要。也就是说SMTP的命令是要组合在一起才能完成一次邮件发送任务,单独调用每个命令的意义不大。POP3命令则不同,LIST、STAT、UIDL、TOP、RETR、DELE等命令都可以独立使用,比如用LIST命令查看邮件清单,然后用RETR命令接收邮件。



简单的另一层含义是:就socket编程而言实现发送数据要比实现接收数据简单点。

比如接收数据时要判断数据是否接收完毕。如果一条数据以回车换行结束,就需要判断是否接收到了"\\r\\n",从而确保读取到一条完整的消息体。而发送数据则不需要考虑上述问题,你可以按照自己的节奏发送数据,可以一次将整个消息体发送出去,也可以不用考虑服务器的死活一个字节一个字节发送数据,直至将整条消息发送完毕。

换句话说,接收数据要以流的方式进行,而不是简单的开辟一个缓冲区,进行一次recv操作。 虽然大部分情况下这种方式也没有问题,比如写个Demo程序,但如果要让你的网络程序非常健壮的话,最好以流的方式进行读取。因为并不是每次对方都会按照你期望的方式发送数据给你,比如,你开辟了1024字节缓冲区用于接收网络数据,但对方可能一次只给你发送一个字节,或者发出了1025个字节。



SMTP和HTTP协议一样都属于请求应答式协议,也就是一问一答,客户端发送命令后,服务器返回响应内容。 SMTP的响应格式和HTTP协议的基本一样,都是响应码+响应描述。响应码用三位数字表示,空格后则是响应信息的描述,只是HTTP协议会多一个版本信息。

这种一问一答式协议,在HTTP协议上体现的并不是很明显,只有HTTP连接设置为Keep-Alive时,你才有机会使用GET或POST命令反复与服务器进行交互,否则只有一次问答的机会。

但在SMTP协议下这种一问一答的交互方式就非常明显了。 主要原因是完成一次邮件的发送任务涉及到的步骤比较多,我把电子邮件的发送分为如下五个步骤:

https://zhidao.baixing.com/question/13138274.html

https://zhidao.baixing.com/question/13138275.html

https://zhidao.baixing.com/question/13138276.html

https://zhidao.baixing.com/question/13138277.html

https://zhidao.baixing.com/question/13138278.html

https://zhidao.baixing.com/question/13138279.html

https://zhidao.baixing.com/question/13138280.html

https://zhidao.baixing.com/question/13138281.html

https://zhidao.baixing.com/question/13138282.html

https://zhidao.baixing.com/question/13138283.html

https://zhidao.baixing.com/question/13138284.html

https://zhidao.baixing.com/question/13138285.html

https://zhidao.baixing.com/question/13138286.html

https://zhidao.baixing.com/question/13138287.html

https://zhidao.baixing.com/question/13138288.html

https://zhidao.baixing.com/question/13138289.html

https://zhidao.baixing.com/question/13138290.html

https://zhidao.baixing.com/question/13138291.html

https://zhidao.baixing.com/question/13138292.html

https://zhidao.baixing.com/question/13138293.html

https://zhidao.baixing.com/question/13138294.html

https://zhidao.baixing.com/question/13138295.html

https://zhidao.baixing.com/question/13138296.html

https://zhidao.baixing.com/question/13138297.html

https://zhidao.baixing.com/question/13138298.html

https://zhidao.baixing.com/question/13138300.html

https://zhidao.baixing.com/question/13138301.html

https://zhidao.baixing.com/question/13138302.html

https://zhidao.baixing.com/question/13138303.html

https://zhidao.baixing.com/question/13138304.html

https://zhidao.baixing.com/question/13138307.html

https://zhidao.baixing.com/question/13138308.html

https://zhidao.baixing.com/question/13138309.html

https://zhidao.baixing.com/question/13138310.html

https://zhidao.baixing.com/question/13138311.html

https://zhidao.baixing.com/question/13138312.html

https://zhidao.baixing.com/question/13138313.html

https://zhidao.baixing.com/question/13138314.html

https://zhidao.baixing.com/question/13138315.html

https://zhidao.baixing.com/question/13138316.html

https://zhidao.baixing.com/question/13138317.html

https://zhidao.baixing.com/question/13138318.html

https://zhidao.baixing.com/question/13138319.html

https://zhidao.baixing.com/question/13138320.html

https://zhidao.baixing.com/question/13138321.html

https://zhidao.baixing.com/question/13138322.html

https://zhidao.baixing.com/question/13138323.html

https://zhidao.baixing.com/question/13138324.html

https://zhidao.baixing.com/question/13138325.html

https://zhidao.baixing.com/question/13138326.html

https://zhidao.baixing.com/question/13138327.html

https://zhidao.baixing.com/question/13138328.html

https://zhidao.baixing.com/question/13138329.html

https://zhidao.baixing.com/question/13138330.html

https://zhidao.baixing.com/question/13138331.html

https://zhidao.baixing.com/question/13138332.html

https://zhidao.baixing.com/question/13138333.html

https://zhidao.baixing.com/question/13138334.html

https://zhidao.baixing.com/question/13138335.html

https://zhidao.baixing.com/question/13138336.html

https://zhidao.baixing.com/question/13138337.html

https://zhidao.baixing.com/question/13138338.html

https://zhidao.baixing.com/question/13138339.html

https://zhidao.baixing.com/question/13138340.html

https://zhidao.baixing.com/question/13138341.html

https://zhidao.baixing.com/question/13138342.html

https://zhidao.baixing.com/question/13138343.html

https://zhidao.baixing.com/question/13138345.html

https://zhidao.baixing.com/question/13138347.html

https://zhidao.baixing.com/question/13138348.html

https://zhidao.baixing.com/question/13138349.html

https://zhidao.baixing.com/question/13138350.html

https://zhidao.baixing.com/question/13138351.html

https://zhidao.baixing.com/question/13138352.html

https://zhidao.baixing.com/question/13138353.html

https://zhidao.baixing.com/question/13138354.html

https://zhidao.baixing.com/question/13138355.html

https://zhidao.baixing.com/question/13138356.html

https://zhidao.baixing.com/question/13138358.html

https://zhidao.baixing.com/question/13138359.html

https://zhidao.baixing.com/question/13138360.html

https://zhidao.baixing.com/question/13138361.html

https://zhidao.baixing.com/question/13138362.html

https://zhidao.baixing.com/question/13138363.html

https://zhidao.baixing.com/question/13138364.html

https://zhidao.baixing.com/question/13138365.html

https://zhidao.baixing.com/question/13138366.html

https://zhidao.baixing.com/question/13138367.html

https://zhidao.baixing.com/question/13138368.html

https://zhidao.baixing.com/question/13138369.html

https://zhidao.baixing.com/question/13138370.html

https://zhidao.baixing.com/question/13138371.html

https://zhidao.baixing.com/question/13138372.html

https://zhidao.baixing.com/question/13138373.html

https://zhidao.baixing.com/question/13138374.html

https://zhidao.baixing.com/question/13138375.html

https://zhidao.baixing.com/question/13138376.html

https://zhidao.baixing.com/question/13138377.html

https://zhidao.baixing.com/question/13138378.html

https://zhidao.baixing.com/question/13138379.html

https://zhidao.baixing.com/question/13138380.html

https://zhidao.baixing.com/question/13138381.html

https://zhidao.baixing.com/question/13138382.html

https://zhidao.baixing.com/question/13138383.html

https://zhidao.baixing.com/question/13138384.html

https://zhidao.baixing.com/question/13138385.html

https://zhidao.baixing.com/question/13138386.html

【SMTP和HTTP协议一样都属于请求应答式协议】https://zhidao.baixing.com/question/13138387.html

https://zhidao.baixing.com/question/13138388.html

https://zhidao.baixing.com/question/13138389.html

https://zhidao.baixing.com/question/13138390.html

https://zhidao.baixing.com/question/13138391.html

https://zhidao.baixing.com/question/13138392.html

https://zhidao.baixing.com/question/13138393.html

https://zhidao.baixing.com/question/13138394.html

https://zhidao.baixing.com/question/13138395.html

https://zhidao.baixing.com/question/13138396.html

https://zhidao.baixing.com/question/13138397.html

https://zhidao.baixing.com/question/13138398.html

https://zhidao.baixing.com/question/13138399.html

https://zhidao.baixing.com/question/13138400.html

https://zhidao.baixing.com/question/13138401.html

https://zhidao.baixing.com/question/13138402.html

https://zhidao.baixing.com/question/13138403.html

https://zhidao.baixing.com/question/13138404.html

https://zhidao.baixing.com/question/13138405.html

https://zhidao.baixing.com/question/13138406.html

https://zhidao.baixing.com/question/13138407.html

https://zhidao.baixing.com/question/13138408.html

https://zhidao.baixing.com/question/13138409.html

https://zhidao.baixing.com/question/13138410.html

https://zhidao.baixing.com/question/13138411.html

https://zhidao.baixing.com/question/13138412.html

https://zhidao.baixing.com/question/13138413.html

https://zhidao.baixing.com/question/13138414.html

https://zhidao.baixing.com/question/13138415.html

https://zhidao.baixing.com/question/13138416.html

https://zhidao.baixing.com/question/13138417.html

https://zhidao.baixing.com/question/13138418.html

https://zhidao.baixing.com/question/13138419.html

https://zhidao.baixing.com/question/13138420.html

https://zhidao.baixing.com/question/13138421.html

https://zhidao.baixing.com/question/13138422.html

https://zhidao.baixing.com/question/13138423.html

https://zhidao.baixing.com/question/13138424.html

https://zhidao.baixing.com/question/13138425.html

https://zhidao.baixing.com/question/13138426.html

https://zhidao.baixing.com/question/13138427.html

https://zhidao.baixing.com/question/13138429.html

https://zhidao.baixing.com/question/13138430.html

https://zhidao.baixing.com/question/13138431.html

https://zhidao.baixing.com/question/13138432.html

https://zhidao.baixing.com/question/13138433.html

https://zhidao.baixing.com/question/13138434.html

https://zhidao.baixing.com/question/13138435.html

https://zhidao.baixing.com/question/13138436.html

https://zhidao.baixing.com/question/13138437.html

https://zhidao.baixing.com/question/13138438.html

https://zhidao.baixing.com/question/13138439.html

https://zhidao.baixing.com/question/13138440.html

https://zhidao.baixing.com/question/13138441.html

https://zhidao.baixing.com/question/13138442.html

https://zhidao.baixing.com/question/13138443.html

https://zhidao.baixing.com/question/13138444.html

https://zhidao.baixing.com/question/13138445.html

https://zhidao.baixing.com/question/13138446.html

https://zhidao.baixing.com/question/13138447.html

https://zhidao.baixing.com/question/13138448.html

https://zhidao.baixing.com/question/13138449.html

https://zhidao.baixing.com/question/13138450.html

https://zhidao.baixing.com/question/13138451.html

https://zhidao.baixing.com/question/13138452.html

https://zhidao.baixing.com/question/13138453.html

https://zhidao.baixing.com/question/13138454.html

https://zhidao.baixing.com/question/13138455.html

https://zhidao.baixing.com/question/13138457.html

https://zhidao.baixing.com/question/13138458.html

https://zhidao.baixing.com/question/13138459.html

https://zhidao.baixing.com/question/13138460.html

https://zhidao.baixing.com/question/13138461.html

https://zhidao.baixing.com/question/13138462.html

https://zhidao.baixing.com/question/13138463.html

https://zhidao.baixing.com/question/13138464.html

https://zhidao.baixing.com/question/13138465.html

https://zhidao.baixing.com/question/13138466.html

https://zhidao.baixing.com/question/13138467.html

https://zhidao.baixing.com/question/13138468.html

https://zhidao.baixing.com/question/13138469.html

https://zhidao.baixing.com/question/13138470.html

https://zhidao.baixing.com/question/13138471.html

https://zhidao.baixing.com/question/13138472.html

https://zhidao.baixing.com/question/13138473.html

https://zhidao.baixing.com/question/13138474.html

https://zhidao.baixing.com/question/13138475.html

https://zhidao.baixing.com/question/13138476.html

https://zhidao.baixing.com/question/13138477.html

https://zhidao.baixing.com/question/13138478.html

https://zhidao.baixing.com/question/13138479.html

https://zhidao.baixing.com/question/13138480.html

https://zhidao.baixing.com/question/13138481.html

https://zhidao.baixing.com/question/13138482.html

https://zhidao.baixing.com/question/13138483.html

https://zhidao.baixing.com/question/13138484.html

https://zhidao.baixing.com/question/13138485.html

https://zhidao.baixing.com/question/13138487.html

https://zhidao.baixing.com/question/13138488.html

https://zhidao.baixing.com/question/13138489.html

https://zhidao.baixing.com/question/13138490.html

https://zhidao.baixing.com/question/13138491.html

https://zhidao.baixing.com/question/13138492.html

https://zhidao.baixing.com/question/13138493.html

https://zhidao.baixing.com/question/13138494.html

https://zhidao.baixing.com/question/13138495.html

https://zhidao.baixing.com/question/13138496.html

https://zhidao.baixing.com/question/13138497.html

https://zhidao.baixing.com/question/13138498.html

https://zhidao.baixing.com/question/13138499.html

https://zhidao.baixing.com/question/13138500.html

https://zhidao.baixing.com/question/13138501.html

https://zhidao.baixing.com/question/13138502.html

https://zhidao.baixing.com/question/13138503.html

https://zhidao.baixing.com/question/13138504.html

https://zhidao.baixing.com/question/13138505.html

https://zhidao.baixing.com/question/13138506.html

https://zhidao.baixing.com/question/13138507.html

https://zhidao.baixing.com/question/13138508.html

https://zhidao.baixing.com/question/13138509.html

https://zhidao.baixing.com/question/13138510.html

https://zhidao.baixing.com/question/13138511.html

https://zhidao.baixing.com/question/13138512.html

https://zhidao.baixing.com/question/13138513.html

https://zhidao.baixing.com/question/13138514.html

https://zhidao.baixing.com/question/13138515.html

https://zhidao.baixing.com/question/13138516.html

https://zhidao.baixing.com/question/13138517.html

https://zhidao.baixing.com/question/13138518.html

https://zhidao.baixing.com/question/13138520.html

https://zhidao.baixing.com/question/13138521.html

https://zhidao.baixing.com/question/13138522.html

https://zhidao.baixing.com/question/13138523.html

https://zhidao.baixing.com/question/13138524.html

https://zhidao.baixing.com/question/13138526.html

https://zhidao.baixing.com/question/13138527.html

https://zhidao.baixing.com/question/13138528.html

https://zhidao.baixing.com/question/13138529.html

https://zhidao.baixing.com/question/13138531.html

https://zhidao.baixing.com/question/13138532.html

https://zhidao.baixing.com/question/13138533.html

https://zhidao.baixing.com/question/13138534.html

https://zhidao.baixing.com/question/13138535.html

https://zhidao.baixing.com/question/13138536.html

https://zhidao.baixing.com/question/13138537.html

https://zhidao.baixing.com/question/13138538.html

https://zhidao.baixing.com/question/13138539.html

https://zhidao.baixing.com/question/13138540.html

https://zhidao.baixing.com/question/13138541.html

https://zhidao.baixing.com/question/13138542.html

https://zhidao.baixing.com/question/13138543.html

https://zhidao.baixing.com/question/13138544.html

https://zhidao.baixing.com/question/13138545.html

https://zhidao.baixing.com/question/13138546.html

https://zhidao.baixing.com/question/13138547.html

https://zhidao.baixing.com/question/13138548.html

https://zhidao.baixing.com/question/13138549.html

https://zhidao.baixing.com/question/13138550.html

https://zhidao.baixing.com/question/13138551.html

https://zhidao.baixing.com/question/13138552.html

https://zhidao.baixing.com/question/13138554.html

https://zhidao.baixing.com/question/13138555.html

https://zhidao.baixing.com/question/13138556.html

https://zhidao.baixing.com/question/13138557.html

https://zhidao.baixing.com/question/13138558.html

https://zhidao.baixing.com/question/13138559.html

https://zhidao.baixing.com/question/13138561.html

https://zhidao.baixing.com/question/13138562.html

https://zhidao.baixing.com/question/13138563.html

https://zhidao.baixing.com/question/13138564.html

https://zhidao.baixing.com/question/13138565.html

https://zhidao.baixing.com/question/13138566.html

https://zhidao.baixing.com/question/13138567.html

https://zhidao.baixing.com/question/13138568.html

https://zhidao.baixing.com/question/13138569.html

https://zhidao.baixing.com/question/13138571.html

https://zhidao.baixing.com/question/13138572.html

https://zhidao.baixing.com/question/13138574.html

https://zhidao.baixing.com/question/13138575.html

https://zhidao.baixing.com/question/13138576.html

https://zhidao.baixing.com/question/13138577.html

https://zhidao.baixing.com/question/13138578.html

https://zhidao.baixing.com/question/13138579.html

https://zhidao.baixing.com/question/13138580.html

https://zhidao.baixing.com/question/13138581.html

https://zhidao.baixing.com/question/13138582.html

https://zhidao.baixing.com/question/13138584.html

https://zhidao.baixing.com/question/13138585.html

https://zhidao.baixing.com/question/13138586.html

https://zhidao.baixing.com/question/13138587.html

https://zhidao.baixing.com/question/13138588.html

https://zhidao.baixing.com/question/13138589.html

https://zhidao.baixing.com/question/13138590.html

https://zhidao.baixing.com/question/13138591.html

https://zhidao.baixing.com/question/13138592.html

https://zhidao.baixing.com/question/13138593.html

https://zhidao.baixing.com/question/13138594.html

https://zhidao.baixing.com/question/13138595.html

https://zhidao.baixing.com/question/13138596.html

https://zhidao.baixing.com/question/13138597.html

https://zhidao.baixing.com/question/13138598.html

https://zhidao.baixing.com/question/13138599.html

https://zhidao.baixing.com/question/13138600.html

https://zhidao.baixing.com/question/13138601.html

https://zhidao.baixing.com/question/13138602.html

https://zhidao.baixing.com/question/13138603.html

https://zhidao.baixing.com/question/13138604.html

https://zhidao.baixing.com/question/13138606.html

https://zhidao.baixing.com/question/13138607.html

https://zhidao.baixing.com/question/13138608.html

https://zhidao.baixing.com/question/13138609.html

https://zhidao.baixing.com/question/13138610.html

https://zhidao.baixing.com/question/13138611.html

https://zhidao.baixing.com/question/13138612.html

https://zhidao.baixing.com/question/13138613.html

https://zhidao.baixing.com/question/13138614.html

https://zhidao.baixing.com/question/13138615.html

https://zhidao.baixing.com/question/13138616.html

https://zhidao.baixing.com/question/13138617.html

https://zhidao.baixing.com/question/13138618.html

https://zhidao.baixing.com/question/13138619.html

https://zhidao.baixing.com/question/13138620.html

https://zhidao.baixing.com/question/13138621.html

https://zhidao.baixing.com/question/13138622.html

https://zhidao.baixing.com/question/13138623.html

https://zhidao.baixing.com/question/13138624.html

https://zhidao.baixing.com/question/13138626.html

https://zhidao.baixing.com/question/13138627.html

https://zhidao.baixing.com/question/13138628.html

https://zhidao.baixing.com/question/13138629.html

https://zhidao.baixing.com/question/13138630.html

https://zhidao.baixing.com/question/13138631.html

https://zhidao.baixing.com/question/13138632.html

https://zhidao.baixing.com/question/13138633.html

https://zhidao.baixing.com/question/13138634.html

https://zhidao.baixing.com/question/13138635.html

https://zhidao.baixing.com/question/13138636.html

https://zhidao.baixing.com/question/13138637.html

https://zhidao.baixing.com/question/13138638.html

https://zhidao.baixing.com/question/13138639.html

https://zhidao.baixing.com/question/13138640.html

https://zhidao.baixing.com/question/13138641.html

https://zhidao.baixing.com/question/13138642.html

https://zhidao.baixing.com/question/13138643.html

https://zhidao.baixing.com/question/13138644.html

https://zhidao.baixing.com/question/13138645.html

https://zhidao.baixing.com/question/13138646.html

https://zhidao.baixing.com/question/13138647.html

https://zhidao.baixing.com/question/13138648.html

https://zhidao.baixing.com/question/13138649.html

https://zhidao.baixing.com/question/13138650.html

https://zhidao.baixing.com/question/13138651.html

https://zhidao.baixing.com/question/13138652.html

https://zhidao.baixing.com/question/13138653.html

https://zhidao.baixing.com/question/13138655.html

https://zhidao.baixing.com/question/13138656.html

https://zhidao.baixing.com/question/13138657.html

https://zhidao.baixing.com/question/13138658.html

https://zhidao.baixing.com/question/13138659.html

https://zhidao.baixing.com/question/13138660.html

https://zhidao.baixing.com/question/13138661.html

https://zhidao.baixing.com/question/13138662.html

https://zhidao.baixing.com/question/13138663.html

https://zhidao.baixing.com/question/13138664.html

https://zhidao.baixing.com/question/13138665.html

https://zhidao.baixing.com/question/13138666.html

https://zhidao.baixing.com/question/13138667.html

https://zhidao.baixing.com/question/13138668.html

https://zhidao.baixing.com/question/13138669.html

https://zhidao.baixing.com/question/13138670.html

https://zhidao.baixing.com/question/13138672.html

https://zhidao.baixing.com/question/13138673.html

https://zhidao.baixing.com/question/13138674.html

https://zhidao.baixing.com/question/13138675.html

https://zhidao.baixing.com/question/13138676.html

https://zhidao.baixing.com/question/13138677.html

https://zhidao.baixing.com/question/13138678.html

https://zhidao.baixing.com/question/13138679.html

https://zhidao.baixing.com/question/13138680.html

https://zhidao.baixing.com/question/13138681.html

https://zhidao.baixing.com/question/13138682.html

https://zhidao.baixing.com/question/13138683.html

https://zhidao.baixing.com/question/13138684.html

https://zhidao.baixing.com/question/13138686.html

https://zhidao.baixing.com/question/13138687.html

https://zhidao.baixing.com/question/13138688.html

https://zhidao.baixing.com/question/13138689.html

https://zhidao.baixing.com/question/13138690.html

https://zhidao.baixing.com/question/13138691.html

https://zhidao.baixing.com/question/13138692.html

https://zhidao.baixing.com/question/13138693.html

https://zhidao.baixing.com/question/13138694.html

https://zhidao.baixing.com/question/13138695.html

https://zhidao.baixing.com/question/13138696.html

https://zhidao.baixing.com/question/13138697.html

https://zhidao.baixing.com/question/13138698.html

https://zhidao.baixing.com/question/13138699.html

https://zhidao.baixing.com/question/13138700.html

https://zhidao.baixing.com/question/13138701.html

https://zhidao.baixing.com/question/13138702.html

https://zhidao.baixing.com/question/13138703.html

https://zhidao.baixing.com/question/13138704.html

https://zhidao.baixing.com/question/13138705.html

https://zhidao.baixing.com/question/13138706.html

https://zhidao.baixing.com/question/13138707.html

https://zhidao.baixing.com/question/13138708.html

https://zhidao.baixing.com/question/13138709.html

https://zhidao.baixing.com/question/13138710.html

https://zhidao.baixing.com/question/13138711.html

https://zhidao.baixing.com/question/13138713.html

https://zhidao.baixing.com/question/13138714.html

https://zhidao.baixing.com/question/13138715.html

https://zhidao.baixing.com/question/13138716.html

https://zhidao.baixing.com/question/13138717.html

https://zhidao.baixing.com/question/13138718.html

https://zhidao.baixing.com/question/13138719.html

https://zhidao.baixing.com/question/13138720.html

https://zhidao.baixing.com/question/13138721.html

https://zhidao.baixing.com/question/13138722.html

https://zhidao.baixing.com/question/13138723.html

https://zhidao.baixing.com/question/13138724.html

https://zhidao.baixing.com/question/13138725.html

https://zhidao.baixing.com/question/13138726.html

https://zhidao.baixing.com/question/13138727.html

https://zhidao.baixing.com/question/13138728.html

https://zhidao.baixing.com/question/13138729.html

https://zhidao.baixing.com/question/13138730.html

https://zhidao.baixing.com/question/13138731.html

https://zhidao.baixing.com/question/13138732.html

https://zhidao.baixing.com/question/13138733.html

https://zhidao.baixing.com/question/13138734.html

https://zhidao.baixing.com/question/13138735.html

https://zhidao.baixing.com/question/13138736.html

https://zhidao.baixing.com/question/13138737.html

https://zhidao.baixing.com/question/13138739.html

https://zhidao.baixing.com/question/13138740.html

https://zhidao.baixing.com/question/13138741.html

https://zhidao.baixing.com/question/13137849.html

https://zhidao.baixing.com/question/13137923.html

https://zhidao.baixing.com/question/13137933.html

https://zhidao.baixing.com/question/13138051.html

https://zhidao.baixing.com/question/13138075.html

https://zhidao.baixing.com/question/13138092.html

https://zhidao.baixing.com/question/13138095.html

https://zhidao.baixing.com/question/13138099.html

https://zhidao.baixing.com/question/13138100.html

https://zhidao.baixing.com/question/13138101.html

https://zhidao.baixing.com/question/13138102.html

https://zhidao.baixing.com/question/13138104.html

https://zhidao.baixing.com/question/13138105.html

https://zhidao.baixing.com/question/13138106.html

https://zhidao.baixing.com/question/13138107.html

https://zhidao.baixing.com/question/13138108.html

https://zhidao.baixing.com/question/13138109.html

https://zhidao.baixing.com/question/13138110.html

https://zhidao.baixing.com/question/13138111.html

https://zhidao.baixing.com/question/13138112.html

https://zhidao.baixing.com/question/13138113.html

https://zhidao.baixing.com/question/13138114.html

https://zhidao.baixing.com/question/13138115.html

https://zhidao.baixing.com/question/13138116.html

https://zhidao.baixing.com/question/13138117.html

https://zhidao.baixing.com/question/13138118.html

https://zhidao.baixing.com/question/13138119.html

https://zhidao.baixing.com/question/13138120.html

https://zhidao.baixing.com/question/13138121.html

https://zhidao.baixing.com/question/13138122.html

https://zhidao.baixing.com/question/13138123.html

https://zhidao.baixing.com/question/13138124.html

https://zhidao.baixing.com/question/13138125.html

https://zhidao.baixing.com/question/13138127.html

https://zhidao.baixing.com/question/13138128.html

https://zhidao.baixing.com/question/13138129.html

https://zhidao.baixing.com/question/13138130.html

https://zhidao.baixing.com/question/13138131.html

https://zhidao.baixing.com/question/13138132.html

https://zhidao.baixing.com/question/13138133.html

https://zhidao.baixing.com/question/13138135.html

https://zhidao.baixing.com/question/13138136.html

https://zhidao.baixing.com/question/13138137.html

https://zhidao.baixing.com/question/13138138.html

https://zhidao.baixing.com/question/13138139.html

https://zhidao.baixing.com/question/13138140.html

https://zhidao.baixing.com/question/13138141.html

https://zhidao.baixing.com/question/13138142.html

https://zhidao.baixing.com/question/13138152.html

https://zhidao.baixing.com/question/13138153.html

https://zhidao.baixing.com/question/13138154.html

https://zhidao.baixing.com/question/13138156.html

https://zhidao.baixing.com/question/13138157.html

https://zhidao.baixing.com/question/13138158.html

https://zhidao.baixing.com/question/13138159.html

https://zhidao.baixing.com/question/13138160.html

https://zhidao.baixing.com/question/13138161.html

https://zhidao.baixing.com/question/13138162.html

https://zhidao.baixing.com/question/13138163.html

https://zhidao.baixing.com/question/13138164.html

https://zhidao.baixing.com/question/13138165.html

https://zhidao.baixing.com/question/13138166.html

https://zhidao.baixing.com/question/13138167.html

https://zhidao.baixing.com/question/13138168.html

https://zhidao.baixing.com/question/13138169.html

https://zhidao.baixing.com/question/13138170.html

https://zhidao.baixing.com/question/13138171.html

https://zhidao.baixing.com/question/13138172.html

https://zhidao.baixing.com/question/13138173.html

https://zhidao.baixing.com/question/13138174.html

https://zhidao.baixing.com/question/13138175.html

https://zhidao.baixing.com/question/13138176.html

https://zhidao.baixing.com/question/13138177.html

https://zhidao.baixing.com/question/13138178.html

https://zhidao.baixing.com/question/13138179.html

https://zhidao.baixing.com/question/13138181.html

https://zhidao.baixing.com/question/13138182.html

https://zhidao.baixing.com/question/13138183.html

https://zhidao.baixing.com/question/13138184.html

https://zhidao.baixing.com/question/13138185.html

https://zhidao.baixing.com/question/13138186.html

https://zhidao.baixing.com/question/13138187.html

https://zhidao.baixing.com/question/13138188.html

https://zhidao.baixing.com/question/13138189.html

https://zhidao.baixing.com/question/13138190.html

https://zhidao.baixing.com/question/13138191.html

https://zhidao.baixing.com/question/13138192.html

https://zhidao.baixing.com/question/13138193.html

https://zhidao.baixing.com/question/13138195.html

https://zhidao.baixing.com/question/13138197.html

https://zhidao.baixing.com/question/13138198.html

https://zhidao.baixing.com/question/13138199.html

https://zhidao.baixing.com/question/13138200.html

https://zhidao.baixing.com/question/13138201.html

https://zhidao.baixing.com/question/13138202.html

https://zhidao.baixing.com/question/13138203.html

https://zhidao.baixing.com/question/13138204.html

https://zhidao.baixing.com/question/13138205.html

https://zhidao.baixing.com/question/13138206.html

https://zhidao.baixing.com/question/13138207.html

https://zhidao.baixing.com/question/13138208.html

https://zhidao.baixing.com/question/13138209.html

https://zhidao.baixing.com/question/13138210.html

https://zhidao.baixing.com/question/13138211.html

https://zhidao.baixing.com/question/13138213.html

https://zhidao.baixing.com/question/13138214.html

https://zhidao.baixing.com/question/13138215.html

https://zhidao.baixing.com/question/13138216.html

https://zhidao.baixing.com/question/13138217.html

https://zhidao.baixing.com/question/13138218.html

https://zhidao.baixing.com/question/13138219.html

https://zhidao.baixing.com/question/13138220.html

https://zhidao.baixing.com/question/13138221.html

https://zhidao.baixing.com/question/13138222.html

https://zhidao.baixing.com/question/13138223.html

https://zhidao.baixing.com/question/13138224.html

https://zhidao.baixing.com/question/13138225.html

https://zhidao.baixing.com/question/13138226.html

https://zhidao.baixing.com/question/13138227.html

https://zhidao.baixing.com/question/13138228.html

https://zhidao.baixing.com/question/13138229.html

https://zhidao.baixing.com/question/13138230.html

https://zhidao.baixing.com/question/13138231.html

https://zhidao.baixing.com/question/13138232.html

https://zhidao.baixing.com/question/13138233.html

https://zhidao.baixing.com/question/13138234.html

https://zhidao.baixing.com/question/13138235.html

https://zhidao.baixing.com/question/13138236.html

https://zhidao.baixing.com/question/13138237.html

https://zhidao.baixing.com/question/13138238.html

https://zhidao.baixing.com/question/13138239.html

https://zhidao.baixing.com/question/13138240.html

https://zhidao.baixing.com/question/13138241.html

https://zhidao.baixing.com/question/13138242.html

https://zhidao.baixing.com/question/13138244.html

https://zhidao.baixing.com/question/13138245.html

https://zhidao.baixing.com/question/13138246.html

https://zhidao.baixing.com/question/13138247.html

https://zhidao.baixing.com/question/13138248.html

https://zhidao.baixing.com/question/13138249.html

https://zhidao.baixing.com/question/13138251.html

https://zhidao.baixing.com/question/13138252.html

https://zhidao.baixing.com/question/13138253.html

https://zhidao.baixing.com/question/13138254.html

https://zhidao.baixing.com/question/13138255.html

https://zhidao.baixing.com/question/13138256.html

https://zhidao.baixing.com/question/13138257.html

https://zhidao.baixing.com/question/13138258.html

https://zhidao.baixing.com/question/13138259.html

https://zhidao.baixing.com/question/13138260.html

https://zhidao.baixing.com/question/13138261.html

https://zhidao.baixing.com/question/13138262.html

https://zhidao.baixing.com/question/13138263.html

https://zhidao.baixing.com/question/13138264.html

https://zhidao.baixing.com/question/13138265.html

https://zhidao.baixing.com/question/13138266.html

    推荐阅读