ASP.NET保持用户状态的九种选择(上)

＜h1＞Form 1＜/h1＞
＜form id="Application" method="post" runat="server"＞
＜p＞Your username:
＜asp:Label ID="lblUsername" Runat="server" /＞
＜/p＞
＜asp:Panel Runat="server" ID="pnlSetValue"＞
＜asp:validationsummary id="valSummary" Runat="server"＞
＜/asp:validationsummary＞
＜TABLE＞
＜TR＞
＜TD colSpan="3"＞Set Hidden Form Username Variable:＜/TD＞＜/TR＞
＜TR＞
＜TD＞Username＜/TD＞
＜TD＞
＜asp:textbox id="txtName" Runat="server"＞＜/asp:textbox＞＜/TD＞
＜TD＞
＜asp:requiredfieldvalidator id="nameRequired" runat="server"
ControlToValidate="txtName" ErrorMessage="Name is required."
Display="Dynamic"＞*＜/asp:requiredfieldvalidator＞＜/TD＞＜/TR＞
＜TR＞
＜TD colSpan="3"＞
＜asp:button id="btnSubmit" Runat="server" Text="Set Value"＞
＜/asp:button＞＜/TD＞＜/TR＞＜/TABLE＞
＜/asp:Panel＞
＜asp:Label ID="lblResult" Runat="server" /＞
＜/form＞
＜form action="form2.aspx" method="post" name="form2" id="form2"＞
＜input type="hidden" name="username" value="＜%# username %＞" ＞
＜input type="submit" value="Go to Form2.aspx"
＜/form＞
Form1.aspx.cs
private void Page_Load(object sender, System.EventArgs e)
{
if(!IsPostBack) // 新的请求或者来自form2.aspx的请求
{
// 检查窗体集合
if(Request.Form["username"] == null)
pnlSetValue.Visible = true;
else
{
//需要设置用户名值
pnlSetValue.Visible = false;
username = Request.Form["username"].ToString();
lblUsername.Text = username;
//数据绑定到隐藏的窗体字段值
this.DataBind();
}
}
}

private void btnSubmit_Click(object sender, System.EventArgs e)
{
if(IsValid)
{
//隐藏窗体来设置值
pnlSetValue.Visible = false;
username = txtName.Text;
lblResult.Text = "Username set to " + txtName.Text + ".";
lblUsername.Text = username;
this.DataBind();
}
}
Form2.aspx
＜h1＞Form 2＜/h1＞
＜form id="Application" method="post" runat="server"＞
＜p＞Your username: ＜asp:Label ID="lblUsername" Runat="server" /＞＜/p＞
＜/form＞
＜form action="form1.aspx" method="post" id="form2" name="form2"＞
＜input type="hidden" name="username" value="＜%# username %＞" ＞
＜input type="submit" value="Go to Form1.aspx"
＜/form＞
Form2.aspx.cs
private void Page_Load(object sender, System.EventArgs e)
{
if(Request.Form["username"] != null)
{
username = Request.Form["username"].ToString();
lblUsername.Text = username;
this.DataBind();
}
}