asp.net 防恶意刷新 多次点击按钮的方法

前台：

<asp:button runat="server" text="Button" OnClick="aa_Click" />

后台

public void page_load(Object obj, EventArgs e)

{

btn.Attributes.Add("onclick", "state=true;");

StringBuilder sb = new StringBuilder();

sb.Append("if (!state) return;");

sb.Append("var button=document.getElementById('btn');");

sb.Append("button.value='Please Wait...';");

sb.Append("document.body.style.cursor='wait';");

sb.Append("button.disabled=true;");

string strScript = "<script>";

strScript = strScript + "var state=false;";

//将函数绑定到页面的onbeforeunload事件:

strScript = strScript + "window.attachEvent('onbeforeunload',function(){" + sb.ToString() + "});";

strScript = strScript + "</" + "script>";

Page.ClientScript.RegisterStartupScript(typeof(_Default),"onbeforeunload", strScript); //typeof(_Default)为默认的类名，要改的。

}

protected void aa_Click(object sender, EventArgs e)

{

//模拟长时间的按钮处理

System.Threading.Thread.Sleep(2000);

Response.Write("<script>alert('bbbbbb!!');" + "</" + "script>");

}