Question

I have a point in my .NET (VB) application at which the user is prompted to select zero to many documents to be printed, which are spawned off in separate new windows.

The list of documents selected is passed in from the previous page, pipe-delimited, as part of the querystring, which is then split to create a list of documents. My code iterates through this list, builds the new window’s URL dynamically and then spawns the new window. For some reason I’m getting a maximum of two new pop-up windows, regardless of whether the user chose three or more, and the list is being populated fully and properly.

I know that I need a unique key for each window, and that is being built dynamically and appears to be working fine. Code is below. Can anyone spot my error?

TIA
Mike

If Not Request.QueryString("clttr") = Nothing Then

    Dim strURL As String
    Dim ScriptString As String
    Dim txnLttr As String
    Dim i As Integer = 0
    Dim strKey As String
    lstLetters = Split(Request.QueryString("clttr"), "|")

    For Each txnLttr In lstLetters
        strKey = "Letter" & i

        If UCase(Mid(txnLttr, Len(txnLttr) - 2, 3)) = "PDF" Then
            strURL = "PDF_Prep.aspx?Case=" & Session("SelKey") & "&COLL=" & Session("SelKey") & "&UN=" & Session("UserPKey") & "&Letter=" & txnLttr
            ScriptString = "<script language='javascript'>"
            ScriptString += "window.open('" & strURL & "', '_blank');"
            ScriptString += "</script>"
            ClientScript.RegisterStartupScript(Me.GetType, strKey, ScriptString)

        Else
           'Response.Redirect("PrtSngleLttr.asp?Case=" & Session("SelKey") & "&Letter=" & txnLttr)
           'Write code here to split the variable txnLttr into path and Letter name...Once done send appropriate params to MergeDocument.

           If txnLttr.Contains("/") Then
               Dim fileName As String
               Dim filePath As String
               Dim lastIndex As Integer = txnLttr.LastIndexOf("/")
               fileName = Right(txnLttr, txnLttr.Length - (lastIndex + 1))
               filePath = Left(txnLttr, lastIndex)
               strURL = "MergeDocument.aspx?Case=" & Session("SelKey") & "&LetterName=" & fileName & "&LetterPath=" & filePath & "&Mode=MERGE"
               ScriptString = "<script language='javascript'>"
               ScriptString += "window.open('" & strURL & "', '_blank');"
               ScriptString += "</script>"
               ClientScript.RegisterStartupScript(Me.GetType, strKey, ScriptString)

           Else
               strURL = "MergeDocument.aspx?Case=" & Session("SelKey") & "&LetterName=" & txnLttr & "&Mode=MERGE"
               ScriptString = "<script language='javascript'>"
               ScriptString += "window.open('" & strURL & "', '_blank');"
               ScriptString += "</script>"
               ClientScript.RegisterStartupScript(Me.GetType, strKey, ScriptString)
            End If
        End If
        i += 1
        Next
    Else
        Response.Redirect("CaseDetail.aspx?case=" & Session("SelKey") & "&UN=" & Header1.UserNumber)
    End If
End If

Answer 1

I can’t spot your exact error, but it could be that one of the values you are pulling into the URL contains an embedded quote (‘), which would destroy the javascript. Replacing any single quotes with \’ in the URL will resolve this issue.

You are going to have a much easier time tracking the issue down if you have all of the javascript in a single block.

In addition, your existing code creates a lot of strings, which will have an impact in a high usage scenario.

To resolve all three of these issues, I would rewrite your code as follows:

If Not Request.QueryString("clttr") = Nothing Then

    Dim ScriptString As New System.Text.StringBuilder(1000)
    lstLetters = Split(Request.QueryString("clttr"), "|")

    For Each txnLttr As String In lstLetters
        Dim strURL As New Sysem.Text.StringBuilder(500)

        If UCase(Mid(txnLttr, Len(txnLttr) - 2, 3)) = "PDF" Then
            strURL.Append("PDF_Prep.aspx?Case=").Append(Session("SelKey")).Append("&COLL=").Append(Session("SelKey")).Append("&UN=").Append(Session("UserPKey")).Append("&Letter=").Append(txnLttr)
        Else
           If txnLttr.Contains("/") Then
               Dim fileName As String
               Dim filePath As String
               Dim lastIndex As Integer = txnLttr.LastIndexOf("/")
               fileName = Right(txnLttr, txnLttr.Length - (lastIndex + 1))
               filePath = Left(txnLttr, lastIndex)

               strURL.Append("MergeDocument.aspx?Case=").Append(Session("SelKey")).Append("&LetterName=").Append(fileName).Append("&LetterPath=").Append(filePath).Append("&Mode=MERGE")
           Else
               strURL.Append("MergeDocument.aspx?Case=").Append(Session("SelKey")).Append("&LetterName=").Append(txnLttr).Append("&Mode=MERGE")
            End If
        End If

        ScriptString.Append("window.open('").Append(strURL.ToString().Replace("'", "\'")).Append("', '_blank');").AppendLine()
    Next

    ClientScript.RegisterStartupScript(Me.GetType, "Letters", ScriptString.ToString(), True)
Else
    Response.Redirect("CaseDetail.aspx?case=" & Session("SelKey") & "&UN=" & Header1.UserNumber)
End If