Don't know where have gone wrong

hoailing22 · May 20th, 2005, 06:39 AM

Hi, I get this error:

Server Error in '/e-library' Application.
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Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

Line 58: Response.Write("Please type the same new password")
Line 59: End If
Line 60:
Line 61: If Page.IsValid Then
Line 62: Dim con As SqlConnection

Source File: c:\inetpub\wwwroot\e-library\UserPassword.aspx.vb Line: 60

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
   e_library.UserPassword.btnSubmit_Click(Object sender, EventArgs e) in c:\inetpub\wwwroot\e-library\UserPassword.aspx.vb:60
   System.Web.UI.WebControls.Button.OnClick(EventArgs e)
   System.Web.UI.WebControls.Button.System.Web.UI.IPo stBackEventHandler.RaisePostBackEvent(String eventArgument)
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEve ntHandler sourceControl, String eventArgument)
   System.Web.UI.Page.RaisePostBackEvent(NameValueCol lection postData)
   System.Web.UI.Page.ProcessRequestMain() +1292

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Version Information: Microsoft .NET Framework Version:1.1.4322.2032; ASP.NET Version:1.1.4322.2032

Code:

 Private Sub btnSubmit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSubmit.Click
        Dim NewPwd As String
        Dim RetypePwd As String
        NewPwd = NewPwd.Trim
        RetypePwd = RetypePwd.Trim

        If NewPwd.Length < 4 Or NewPwd.Length > 10 Then
            Response.Write("Password must be 4-10 characters!")
        End If

        If RetypePwd <> NewPwd Then
            Response.Write("Please type the same new password")
        End If

        If Page.IsValid Then
            Dim con As SqlConnection
            Dim sql As String
            Dim cmd As SqlCommand
            Dim sb As New StringBuilder
            Dim values As New ArrayList

            sb.Append("UPDATE [User] SET ")
            sb.Append("User_id='{0}', User_Password='{1}'")

            values.Add(txtUserID.Text)
            values.Add(txtNewPwd.Text)

            values.Add(Context.User.Identity.Name)
            sql = String.Format(sb.ToString(), values.ToArray())

            con = New SqlConnection( _
                "data source=(local)\NetSdk;initial catalog=E-Library Records;user id=sa")

            cmd = New SqlCommand(sql, con)
            con.Open()

            Try
                cmd.ExecuteNonQuery()
            Catch ex As Exception
                lblMessage.Visible = True
                lblMessage.Text = "Couldn't change your password."
            Finally
                con.Close()
            End Try
            lblPasswordMessage.Visible = True
            lblPasswordMessage.Text = "You have changed your password successfully."
        End If
    End Sub

Hope somebody can help me.

Thanks!

Irene

spacy · May 20th, 2005, 07:06 AM

This wont work :
        Dim NewPwd As String //here you are declaring the variables
        Dim RetypePwd As String
        NewPwd = NewPwd.Trim //there is no value in the variable NewPwd.
        RetypePwd = RetypePwd.Trim //why are u performing a trim if there is no value in the variable?

       //here u have no value in NewPwd and u are trying to find its length
       //this wont work!
       If NewPwd.Length < 4 Or NewPwd.Length > 10 Then
            Response.Write("Password must be 4-10 characters!")
        End If

You need to assign the values from the appropriate controls into the
variables NewPwd and RetypePwd