Java i ASPX (webform)

Du skal bruge registerstartUpScript funktionen

Public Class WebForm1
    Inherits System.Web.UI.Page
    Protected WithEvents Button1 As System.Web.UI.WebControls.Button

#Region " Web Form Designer Generated Code "
#End Region

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Put user code to initialize the page here
        If Not Page.IsClientScriptBlockRegistered("doConfirm") Then
            Dim buffScriptString As String
            buffScriptString = "<script language='javascript'>" + vbCrLf + _
              "<!-- " + vbCrLf + _
              "function __doConfirm(Button1) { " + vbCrLf + _
              "if (confirm('Click to confirm message')) { " + vbCrLf + _
              " return true; " + vbCrLf + _
              "} return false; } " + vbCrLf + _
              "--> " + vbCrLf + _
              "</script>"

            Page.RegisterClientScriptBlock("doConfirm", buffScriptString)
        End If

        Button1.Attributes("onclick") = "return __doConfirm(this);"
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        showClientMessageBox("You have clicked OK. Start execute other code.")

'continue to execute something if you have clicked OK
'for example msgbox
        Me.RegisterStartupScript("TestJS", _
  "<script language='javascript'>alert('Your code is executing');</script>")
    End Sub

    Private Sub showClientMessageBox(ByVal message As String)
        If Not (Page.IsStartupScriptRegistered("doMessage")) Then
            Dim buffScriptString As String
            buffScriptString = "<script language='javascript'>" + vbCrLf + _
            "<!-- " + vbCrLf + _
            "alert(""" + message + """); " + vbCrLf + _
            "--> " + vbCrLf + _
            "</script>"

            Page.RegisterStartupScript("doMessage", buffScriptString)
        End If
    End Sub
End Class

Tak for hjælpen nu virker det bare