asp.net - 在 VB.NET 中显示警报消息

Question

在我的服务器端代码中，我需要显示一条警报消息并在满足特定条件时停止页面的执行。执行停止，但我没有收到警报消息。我错过了什么？我的代码是这样的。

Try
        If txtAmtRequested.Text > Val(HiddenTotalFeeAmount.Value) Then
            ScriptManager.RegisterClientScriptBlock(Me, GetType(Page), UniqueID,
            "javascript:alert('Total Fee Amount set for this student is - '" & HiddenTotalFeeAmount.Value & "'... Enter Concession Amount lesser than this one..!')", True)
                Exit Function
            End If
        Catch ex As Exception

        End Try

Answer 1

试试这个:

Try
    If txtAmtRequested.Text > Val(HiddenTotalFeeAmount.Value) Then
        ScriptManager.RegisterClientScriptBlock(Me, GetType(Page), UniqueID,
        "javascript:alert('Total Fee Amount set for this student is - " & HiddenTotalFeeAmount.Value & "... Enter Concession Amount lesser than the..!');", True)
            Exit Function
        End If
    Catch ex As Exception

    End Try

插入值时，您在 javascript 中结束了字符串，从而生成了以下 javascript:

javascript:alert('Total Fee Amount set for this student is - ' <Value> '... Enter Concession Amount lesser than the..!');

而不是这样，您必须将值直接插入字符串，或添加“+”来连接字符串:

 javascript:alert('Total Fee Amount set for this student is - <Value> ... Enter Concession Amount lesser than the..!');

或

javascript:alert('Total Fee Amount set for this student is - ' + <Value> + '... Enter Concession Amount lesser than the..!');