check for duplicate before appending to new file

[rcVBA]

I have the code below which searches through an html file and extracts the names of all the images in the html code. The image names are written to an xml file and each image name has a set of xml tags added with it.
The problem is that I don't want to add an image name to the xml file if it has been added previously. I don't know if I can search the xml file or if I need a separate file that is an array or a collection, or . . ??

Function GetRegExResult(strInputData As String) As String
Dim Match, Matches
Dim RegExp As Object
Dim strMatchesFile As String 
Dim sRegPath As String
Dim sRegImageFile As String

sRegPath = ActiveDocument.Path
sRegImageFile = sRegPath + "\ImageNames.txt"

    strMatchesFile = sRegImageFile
    Set RegExp = CreateObject("VBScript.RegExp")
    With RegExp
        .Global = True
        .IgnoreCase = True
        .Pattern = "<img\s*src=""([^""]*)"""
    End With

    Set Matches = RegExp.Execute(strInputData) ' Execute search.
    For Each Match In Matches
Dim strMatchOrig As String
Dim intMatchLength As Integer
intMatchLength = Len(Match)
intMatchLength = intMatchLength - 11
strMatchOrig = Match
strMatchOrig = Mid(strMatchOrig, 11, intMatchLength)
        hFile = FreeFile
        Open strMatchesFile For Append As #hFile
Print #hFile, "<Uses>" + vbNewLine _
+ "<FileName>" + strMatchOrig + "<" + Chr(47) + "FileName>" + vbNewLine _
+ "<MD5>456789<" + Chr(47) + "MD5>" + vbNewLine _
+ "<" + Chr(47) + "Uses>"
        Close #hFile
    Next
End Function

[macropod]

You can easily-enough use the Instr function to test whether the xml file contains your image name. If it returns anything greater than 0, the image name is already there.

[rcVBA]

strMatchesFile is the file that the image names are being stored in. I am trying to use InStr like this:

myNoDupes = InStr(strMatchOrig, strMatchesFile)

but strMatchesFile is searched as the file path and name, how can I search the contents of strMatchesFile? I can do the Instr at the point where strMatchesFile is open for Append As #hFile
I'm having some trouble getting the content of the file instead of the file path/name

[macropod]

No, that's not how you would use Instr. You have to open both file before you can test the xml file's contents with Instr. For example, to test each image from your "ImageNames.txt" file:

Dim I As Long
With #hFile
  For I = 0 To UBound(Split(sRegImageFile, vbCr))
    If InStr(.Text, Split(sRegImageFile, vbCr)(I)) = 0 Then
      'The image name isn't present, so add it.
      'Your code to add the image goes here
    End If
  Next
End With

[rcVBA]

Thank you very much, that worked perfect. It took me awhile to work it into the code but now it is all working great.
Thanks again.