WPF VB.Net Save File Dialog

The Idea

Saving content to a txt file

1. A button on a XAML File
2. Upon clicked, open a save file dialog
3. Choose a file or create new file
4. File created if not exists, data written to file

The Chunks

1. We’re going to create a SaveFileDialog class from .Net to open a save file dialog

    ' Create an instance of the open file dialog box.
    	Dim exportFileDialog As New SaveFileDialog
   

2. Only .txt files allowed, we’re putting a restriction by using filter

   ' Set filter options and filter index.
    exportFileDialog.Filter = "Text Files (*.txt)|*.txt"
   

3. Set the ‘open file’ window title and show it to user

    exportFileDialog.Title = "Save as Text file"
    exportFileDialog.ShowDialog()
   

4. Check if user input valid file name

   If exportFileDialog.FileName <> “” Then

5. Get filename from user input

   Dim selectedfile As String = exportFileDialog.FileName

6. Check if file exists, if not, create file

   If System.IO.File.Exists(selectedfile) <> True Then System.IO.File.Create(selectedfile).Dispose() End If

7. We’re using StreamWriter to write to file, don’t forget to close the stream after use

   Dim objWriter As New System.IO.StreamWriter(selectedfile) objWriter.Write(“Writing to file!!”) objWriter.Close()

The Final Function Code

	Private Function SaveToTextFile() As Boolean
        ' Create an instance of the open file dialog box.
        Dim exportFileDialog As New SaveFileDialog
 
        ' Set filter options and filter index.
        exportFileDialog.Filter = "Text Files (*.txt)|*.txt"
        exportFileDialog.Title = "Save as Text file"
        exportFileDialog.ShowDialog()
 
        ' Call the ShowDialog method to show the dialogbox.
        If exportFileDialog.FileName <> "" Then
            Dim selectedfile As String = exportFileDialog.FileName
 
            If System.IO.File.Exists(selectedfile) <> True Then
                System.IO.File.Create(selectedfile).Dispose()
            End If
 
            Dim objWriter As New System.IO.StreamWriter(selectedfile)
            objWriter.Write("Writing to file!!")
            
            objWriter.Close()
            MsgBox("Text written to file")
 
        End If
 
        Return True
    End Function