Looping Through Txt Files using VBA - DIR() issue - excel

Question

I have the following code where I am trying to modify some Txt files in a specific folder. I first want to check that the Loop works. However when I run the macro the code can only read the first file and then there is a runtime 5 error at strFileName = Dir(). I am not sure what the problem is. The only issue I can think of is that I am moving the code between two module sheets. The folder location is being saved in a txt box in Sheet 1 of an excel workbook.
Sub Txt_File_Loop()
Public TextFile As String
Dim FolderLocation As String
Dim strFielName As String
Dim SaveLocation As String
'Location is present in a Text box
FolderLocation = Sheets(1).FolderLocationTXTBX.Text
strFileName = Dir(FolderLocation & " \ * ")
Do Until strFileName = ""
TextFile = FolderLocation & "\" & strFileName
Module2.Macro1
strFileName = Dir() 'ERROR is Here
Loop
End Sub
Sub Macro1()
Dim x As String
Open TextFile For Input As #1
Do Until EOF(1)
Line Input #1, textline
x = x & textline
Loop
Close #1
MsgBox x
End Sub

Answer 1

Have a look at these modifications. They seem to correct several things and run through well.
Option Explicit
Sub Txt_File_Loop()
Dim FolderLocation As String
Dim strFileName As String
Dim SaveLocation As String
'Location is present in a Text box
FolderLocation = Sheets(1).FolderLocationTXTBX.Text 'Environ("TMP")
strFileName = Dir(FolderLocation & "\*.txt")
Do Until strFileName = ""
Debug.Print FolderLocation & "\" & strFileName
Module2.Macro1 FolderLocation & "\" & strFileName
strFileName = Dir() 'ERROR is Here
Loop
End Sub
Sub Macro1(sFPFN As String)
Dim x As String, textline As String
Debug.Print sFPFN
Open sFPFN For Input As #1
Do Until EOF(1)
Line Input #1, textline
x = x & textline
Loop
Close #1
MsgBox x
End Sub
I passed the folder and filename name across as a string-type parameter. Also, I don't know why you had the extra spaces in (FolderLocation & " \ * " ; I tightened that up. There were a few misspellings and undeclared variables; these can be avoided with Option Explicit¹ at the top of the module code sheet. Get into the practise of standard indentation with your code. It certainly improves readability if nothing else.
¹ Setting Require Variable Declaration within the VBE's Tools ► Options ► Editor property page will put the Option Explicit statement at the top of each newly created code sheet. This will avoid silly coding mistakes like misspellings as well as influencing you to use the correct variable type in the variable declaration. Variables created on-the-fly without declaration are all of the variant/object type. Using Option Explicit is widely considered 'best practice'.