不能多说因为问题没有描述问题很好，但是通过检查你的代码，似乎content.value应该是content.Value with Capital'V'，第二你应该< asp.textbox>< /asp.textbox> 使用 TextMode =MultiLine并访问其 Text 属性以获取值。

Cant say much because question is not describing problem well,However by inspecting your code it seems that content.value should be content.Value with Capital 'V' , Second you should <asp.textbox></asp.textbox> with TextMode="MultiLine" and access its Text property to get value.