前端js给后台cs 传值 问题

Question

我想通过js给后台C#程序传值 但是值取不到啊 源代码如下：

前台：aspx

 <asp:HiddenField runat="server" id="hell"/>

<asp:Label ID="Label1" runat="server"></asp:Label>

<script type="text/javascript">

var strrr = document.getElementById("hell").value = "hello";

</script>

后台：cs

 protected void Page_Load(object sender, EventArgs e)
{

string sstr = Request["hell"];
// Label1.Text= Request.Params["hell"];
//Label1.Text = this.hell.Value;
if (sstr == "hello")
Label1.Text = "get hello";
else
Label1.Text = "no hello";

}

Answer 1

服务器端运行完毕后才会发送内容到客户度，此时js才运行，要提交才能获取到客户端的值。。

 <asp:HiddenField runat="server" id="hell"/>

<asp:Label ID="Label1" runat="server"></asp:Label>

<script type="text/javascript">

var strrr = document.getElementById("hell").value = "hello";
document.getElementById("hell").form.submit()//////设置好值后提交表单



//你直接用js设置label1的值就好了，干嘛经过服务器
var strrr = document.getElementById("hell").value = "hello";
document.getElementById("Label1").innerHTML=strrr=='hello'?'get hello':'no hello';
</script>