如果您在html页面中使用html文本和按钮，则您应该尝试这样；

if u r using html text and button inside aspx page then u should try like this ;

<input id="customerPhone" name="customerPhone" type="Text" />
<button OnServerClick=" Btn_Click" runat="server" id="Button1" />

//在.cs代码中编写

// In .cs code write

protected void Btn_Click(object sender, EventArgs e)
 {
     string n = String.Format("{0}", Request.Form["customerPhone"]);

 }

在您的html文本中添加runat ="server"并分配htmltextbox.value = textbox.text;

在html标记中添加runat ="server"时，可以在代码隐藏页***问该标记.
要访问html文本框值，您必须编写htmltextbox.value =";

add runat="server" in your html text and assign htmltextbox.value=textbox.text;

when you add runat="server" in html tag, You can access that tag on codebehind page.
to accesss html textbox value you have to write htmltextbox.value="";

您能解释一下何时要在asp.net文本中获取html文本值吗?

can u explain when u want to get html text value in asp.net text ?