>>我的这个简单
//JS:
<script type="text/javascript">
        var x = 0;
        function xx()
        {
            x++;
            if(x==1)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
    </script>//CS:
 protected void Page_Load(object sender, EventArgs e)
 {
        this.Button1.Attributes.Add("onclick", @"JavaScript:return xx();");
 }