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C# C处理回调结果_C#_Javascript_Asp.net_.net_Icallbackeventhandler - Fatal编程技术网

C# C处理回调结果

C# C处理回调结果,c#,javascript,asp.net,.net,icallbackeventhandler,C#,Javascript,Asp.net,.net,Icallbackeventhandler,e 我在以下情况下有点挣扎。我已经在我的网页中实现了ICallBackEventHandler,除了从后端返回的值对于javascript函数来说是不可读的之外,其他一切都运行顺利。在控制台中,post显示正确的返回值,但函数的参数始终为空 public partial class Intro : System.Web.UI.Page, System.Web.UI.ICallbackEventHandler { private string eventType = String.Empty;

e 我在以下情况下有点挣扎。我已经在我的网页中实现了ICallBackEventHandler,除了从后端返回的值对于javascript函数来说是不可读的之外,其他一切都运行顺利。在控制台中,post显示正确的返回值,但函数的参数始终为空

public partial class Intro : System.Web.UI.Page, System.Web.UI.ICallbackEventHandler
{
private string eventType = String.Empty;


    protected void Page_Load(object sender, EventArgs e)
    {

        //ICallBack event handler
        ClientScriptManager cm = Page.ClientScript;
        string cbReference = cm.GetCallbackEventReference(this, "arg", "HandleResult", "");

        string cbScript = "function RaiseEvent(arg){" + cbReference + ";}";
        cm.RegisterClientScriptBlock(this.GetType(), "RaiseEvent", cbScript, true);
        //End of ICallBack event handler
    }


 }

public void RaiseCallbackEvent(string eventArgument)
    {
        eventType = eventArgument;
    }
    public string GetCallbackResult()
    {
        return "simple";
    }
然后在前端,我有以下场景:我使用这个:RaiseEventstart在点击按钮时触发事件,我使用这个函数处理结果:

function HandleResult(arg) {
            alert(arg); // HERE THE ARGUMENT IS ALWAYS NULL OR EMPTY !!!
        }

请帮助我找出为什么这不能正常运行,以及为什么我无法访问返回参数的值。提前感谢。

这通常是由于未使用页面造成的。IsPostBack

protected void Page_Load(object sender, EventArgs e)
{

   if (!Page.IsPostBack)
   {
    //ICallBack event handler
    ClientScriptManager cm = Page.ClientScript;
    string cbReference = cm.GetCallbackEventReference(this, "arg", "HandleResult", "");

    string cbScript = "function RaiseEvent(arg){" + cbReference + ";}";
    cm.RegisterClientScriptBlock(this.GetType(), "RaiseEvent", cbScript, true);
    //End of ICallBack event handler
    }
}

不,这不是问题所在。