Quale controllo ha causato il postback?

Question

Ho due pulsanti:

<asp:Button ID="Button1" runat="server" Text="Button" /> 
<asp:Button ID="Button2" runat="server" Text="Button" /> 

Come è possibile determinare il Pageload che uno di questo due ha causato il postback? C'è una soluzione breve perché so che ci sono solo due controlli che possono causare questo postback?

Answer 1

È possibile utilizzare questo metodo per ottenere il controllo che ha causato il postback:

/// <summary> 
/// Retrieves the control that caused the postback. 
/// </summary> 
/// <param name="page"></param> 
/// <returns></returns> 
private Control GetControlThatCausedPostBack(Page page) 
{ 
    //initialize a control and set it to null 
    Control ctrl = null; 

    //get the event target name and find the control 
    string ctrlName = page.Request.Params.Get("__EVENTTARGET"); 
    if (!String.IsNullOrEmpty(ctrlName)) 
     ctrl = page.FindControl(ctrlName); 

    //return the control to the calling method 
    return ctrl; 
} 

Answer 2

http://geekswithblogs.net/mahesh/archive/2006/06/27/83264.aspx

private string getPostBackControlName() 
    { 
     Control control = null; 
     //first we will check the "__EVENTTARGET" because if post back made by  the controls 
     //which used "_doPostBack" function also available in Request.Form collection. 

     string ctrlname = Page.Request.Params["__EVENTTARGET"]; 
     if (ctrlname != null && ctrlname != String.Empty) 
     { 
      control = Page.FindControl(ctrlname); 
     } 

     // if __EVENTTARGET is null, the control is a button type and we need to 
     // iterate over the form collection to find it 
     else 
     { 
      string ctrlStr = String.Empty; 
      Control c = null; 
      foreach (string ctl in Page.Request.Form) 
      { 
       //handle ImageButton they having an additional "quasi-property" in their Id which identifies 
       //mouse x and y coordinates 
       if (ctl.EndsWith(".x") || ctl.EndsWith(".y")) 
       { 
        ctrlStr = ctl.Substring(0, ctl.Length - 2); 
        c = Page.FindControl(ctrlStr); 
       } 
       else 
       { 
        c = Page.FindControl(ctl); 
       } 
       if (c is System.Web.UI.WebControls.Button || 
         c is System.Web.UI.WebControls.ImageButton) 
       { 
        control = c; 
        break; 
       } 
      } 

     } 
     return control.ID; 
    } 

Answer 3

Questo aiuta a trovare il nome del controllo che ha causato postback in pageload.This mi ha aiutato Speriamo che questo aiuti qualcun altro

<asp:Button ID="Button1" runat="server" Text="Button" 
    OnClientClick = "SetSource(this.id)" /> 

    <asp:ImageButton ID="ImageButton1" runat="server" 
    OnClientClick = "SetSource(this.id)" /> 

      <script type = "text/javascript"> 
      function SetSource(SourceID) 
      { 
    var hidSourceID = 
    document.getElementById("<%=hidSourceID.ClientID%>"); 
    hidSourceID.value = SourceID; 
    } 
    </script> 

on code behind you can get the ID of the function using : 
if (IsPostBack) 
{ 
    string CtrlID = string.Empty; 
    if (Request.Form[hidSourceID.UniqueID] != null && 
     Request.Form[hidSourceID.UniqueID] != string.Empty) 
    { 
    CtrlID = Request.Form[hidSourceID.UniqueID]; 
    } 
}