一段vb代码修改为c#的，在线等，谢谢

Question

Partial Class CallBackEventHandler_vb
    Inherits System.Web.UI.Page
    Implements ICallbackEventHandler    Private _callBackResult As String    Private Sub Page_Load(ByVal source As Object, ByVal e As System.EventArgs)        Dim callBack As String = Page.ClientScript.GetCallbackEventReference(Me, "arg", "ClientCallback", "context", "ClientCallbackError", False)
        Dim clientFunction As String = "function GetChildren(arg, context){ " & callBack & "; }"
        Page.ClientScript.RegisterClientScriptBlock(Me.GetType(), "GetChildren", clientFunction, True)        If Page.IsPostBack AndAlso Not Page.IsCallback Then            Label1.Text = "You Selected: " & Request.Form("ParentDropDown") & ": " & Request.Form("ChildDropDown")
        End If
    End Sub    Public Sub RaiseCallbackEvent(ByVal eventArgument As String) Implements System.Web.UI.ICallbackEventHandler.RaiseCallbackEvent
        Select Case eventArgument            Case "Item 1"
                _callBackResult = "One|Two|Three"
            Case "Item 2"
                _callBackResult = "Four|Five|Six"
            Case "Item 3"
                _callBackResult = "Seven|Eight|Nine"
            Case Else
                _callBackResult = ""
        End Select
    End Sub    Public Function GetCallbackResult() As String Implements System.Web.UI.ICallbackEventHandler.GetCallbackResult
        Return _callBackResult
    End Function
End Class

Answer 1

理解了c#和VB。Net的语法就没有什么问题了dim  as int = int 变量

Answer 2

private void Page_Load(object source, System.EventArgs e) 
{ 
 string callBack = Page.ClientScript.GetCallbackEventReference(this, "arg", "ClientCallback", "context", "ClientCallbackError", false); 
 string clientFunction = "function GetChildren(arg, context){ " + callBack + "; }"; 
 Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "GetChildren", clientFunction, true); 
 if (Page.IsPostBack && !(Page.IsCallback)) { 
   Label1.Text = "You Selected: " + Request.Form("ParentDropDown") + ": " + Request.Form("ChildDropDown"); 
 } 
}

Answer 3

if (eventArgument == "Item 1") { 
 _callBackResult = "One|Two|Three"; 
} else if (eventArgument == "Item 2") { 
 _callBackResult = "Four|Five|Six"; 
} else if (eventArgument == "Item 3") { 
 _callBackResult = "Seven|Eight|Nine"; 
} else { 
 _callBackResult = ""; 
}

Answer 4

public string GetCallbackResult() 
{ 
 return _callBackResult; 
}

Answer 5

主要是下面语句不清楚：
    Implements ICallbackEventHandler
 Public Sub RaiseCallbackEvent(ByVal eventArgument As String) Implements System.Web.UI.ICallbackEventHandler.RaiseCallbackEvent

Answer 6

http://www.developerfusion.co.uk/utilities/convertcsharptovb.aspx

Answer 7

internal class CallBackEventHandler_vb : Page, ICallbackEventHandler
{
    private string _callBackResult;    public string GetCallbackResult()
    {
        return this._callBackResult;
    }    private void Page_Load(object source, EventArgs e)
    {
        string text1 = this.Page.ClientScript.GetCallbackEventReference(this, "arg", "ClientCallback", "context", "ClientCallbackError", false);
        string text2 = "function GetChildren(arg, context){ " + text1 + "; }";
        this.Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "GetChildren", text2, true);
        if (this.Page.IsPostBack && !this.Page.IsCallback)
        {
            this.Label1.Text = "You Selected: " + this.Request.Form["ParentDropDown"] + ": " + this.Request.Form["ChildDropDown"];
        }
    }    public void RaiseCallbackEvent(string eventArgument)
    {
        switch (eventArgument)
        {
            case "Item 1":
                _callBackResult = "One|Two|Three";
                break;
            case "Item 2":
                _callBackResult = "Four|Five|Six";
                break;
            case "Item 3":
                _callBackResult = "Seven|Eight|Nine";
                break;
            default:
                _callBackResult = "";
                break;
        }
    }
}