[RESOLVED] Need help with terminology and file management

[bwquestion]

Hey all,

I have been attempting to learn and use VB2013 and am making fair progress. I try to look things up before I post but sometimes I am not sure what to look for.

I have this code.

Public Class Form1

    Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles ReadTheFile.Click

        Dim OriginalTextFile As String = "C:\Users\Bryant\Google Drive\readthisfile.txt"
        Dim FileText As String
        Dim OTFReader As New System.IO.StreamReader(OriginalTextFile)
        FileText = OTFReader.ReadToEnd
        TextBox.Text = FileText

    End Sub
End Class

It just reads a hard coded text file when a user clicks a button and writes whatever is in the file to the textbox.

What would the code look like that would allow a user to select their own text file and then write the contents of whatever file the user selected into the text box when the button is clicked.
In case I am not clear this will be two steps. One the user selects the file. Two the user clicks the button to write the contents into the box.

If there is a tutorial on this somewhere that may already exist I am fine with being directed to it.

Thanks.

[Edgemeal]

What would the code look like that would allow a user to select their own text file and then write the contents of whatever file the user selected into the text box when the button is clicked.

I normally use, OpeFileDialog , and check the return value, DialogResult and if OK then load text file with File.ReadAllText

Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles ReadTheFile.Click

  Using ofd As New OpenFileDialog
      ofd.Filter = "Text files (*.txt)|*.txt|All files (*.*)|*.*"
      If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
          TextBox1.Text = IO.File.ReadAllText(ofd.FileName)
          'Else
          'MessageBox.Show("No file was selected by user")
      End If
  End Using

End Sub

[jayinthe813]

The OpenFileDialog class does what you are asking. Also condensed the code a bit:

        Using ofd As New OpenFileDialog
            ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
            If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
                TextBox1.Text = My.Computer.FileSystem.ReadAllText(ofd.FileName)
            End If
        End Using

http://msdn.microsoft.com/en-us/libr...v=vs.110).aspx

[bwquestion]

These do not quite seem to do what I am trying to do. The end result should have two buttons. The User would click the first button to select the file to be read. Based on the above recommendations I believe it woudl look something like this:

    Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles SelectAFile.Click

        Using ofd As New OpenFileDialog
            ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
            If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
                Dim FileName As String
                FileName = IO.File.ReadAllText(ofd.FileName)
            End If
        End Using
    End Sub

Now that the user has selected the file I would like to have a second button to use the file selected and read its contents into a string value that can be used for other purposes. Look at how the example is written. I would like a user to be able to select a file of choice and not have to hard code the path. The rest should work the same. Both of the examples seem to be reading the contents directly into a text box. I do not understand enough about VB to know how to use or manipulate the text if it is in a text box. Thanks

[bwquestion]

This is an idea of what I am trying to do.

    Dim FileName As String

    Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles SelectAFile.Click

        Using ofd As New OpenFileDialog
            ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
            If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
                FileName = IO.File.ReadAllText(ofd.FileName)
            End If
        End Using
    End Sub


    Private Sub ReadTheFile_Click_1(sender As Object, e As EventArgs) Handles ReadTheFile.Click

        Dim FileText As String
        Dim OTFReader As New System.IO.StreamReader(Filename)
        FileText = OTFReader.ReadToEnd
        TextBox.Text = FileText

    End Sub

When I clcik the SelectAFile button it seems to work. When I click the ReadThe File button it gives me an error that there are Illegal characters in the path.

[.paul.]

that's an overcomplicated method you're using, but:

FileName = IO.File.ReadAllText(ofd.FileName)

should be:

FileName = ofd.FileName

[jayinthe813]

These do not quite seem to do what I am trying to do. The end result should have two buttons. The User would click the first button to select the file to be read. Based on the above recommendations I believe it woudl look something like this:

    Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles SelectAFile.Click

        Using ofd As New OpenFileDialog
            ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
            If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
                Dim FileName As String
                FileName = IO.File.ReadAllText(ofd.FileName)
            End If
        End Using
    End Sub

Now that the user has selected the file I would like to have a second button to use the file selected and read its contents into a string value that can be used for other purposes. Look at how the example is written. I would like a user to be able to select a file of choice and not have to hard code the path. The rest should work the same. Both of the examples seem to be reading the contents directly into a text box. I do not understand enough about VB to know how to use or manipulate the text if it is in a text box. Thanks

You are almost there:

Dim FileName As String

    Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles SelectAFile.Click

        Using ofd As New OpenFileDialog
            ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
            If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
                FileName = ofd.FileName
            End If
        End Using
    End Sub


    Private Sub ReadTheFile_Click_1(sender As Object, e As EventArgs) Handles ReadTheFile.Click

        TextBox.Text = IO.File.ReadAllText(FileName)

    End Sub

Optionally, you do not have to use StreamReader . StreamReader is more complex than your needs.

[bwquestion]

Thanks again .paul. your correction worked. Tell me about the overcomplicated method. I do not know what that means. It also will not let me rate your post.

[bwquestion]

jayinth813. Where in your example does the code store the information that is read in from the selected file into a string for use at a later time? That is the part I could not figure out.

I use streamreader because I know it will get everything in the file. Things like linereturns and other things that are not necessarily text. When I see something that says ReadAllText it makes me think it would not pick up everything in the file. It may very well be the same thing I just do not know enough about it to use it at this point.

[.paul.]

Thanks again .paul. your correction worked. Tell me about the overcomplicated method. I do not know what that means. It also will not let me rate your post.

As jayinth813 told you:

TextBox.Text = IO.File.ReadAllText(FileName)

jayinth813. Where in your example does the code store the information that is read in from the selected file into a string for use at a later time? That is the part I could not figure out.

It doesn't save the file contents.
The first button just gets the filename which it saves in the FileName variable
The second button reads the file using the saved filename.
No need to use a StreamReader

[.paul.]

readalltext returns everything in the file...

[bwquestion]

I may just be missing something really obvious so please humor me. If I read the contents of the file directly to a textbox, how would I be able to do anything with it. Say we need to replace all the occurrences of something in the file with something else. If it is stored in a string we could do this very easy. If we skip that step we would have to read the file in again to do anything with it. What part am I missing?

[.paul.]

There are 256 possible characters in use on English and us computers, and they all have a textual representation, though depending on which font you use they may appear as spaces.
Windows recognizes all of those characters...

[.paul.]

It is stored in your textbox's .Text property

[bwquestion]

I changed the streamreader to ReadAllText and it does fine. Here is the complete code.

    Dim FileName As String

    Private Sub ReadTheFile_Click(sender As Object, e As EventArgs) Handles SelectAFile.Click

        Using ofd As New OpenFileDialog
            ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
            If ofd.ShowDialog = Windows.Forms.DialogResult.OK Then
                FileName = ofd.FileName
            End If
        End Using
    End Sub


    Private Sub ReadTheFile_Click_1(sender As Object, e As EventArgs) Handles ReadTheFile.Click

        Dim FileText As String
        FileText = IO.File.ReadAllText(FileName)
        TextBox.Text = FileText

    End Sub

[.paul.]

You know how to use a Form level variable. You used that for FileName. It's not a giant leap to see how you could store a file's contents in another variable...

[bwquestion]

I would not feel safe leaving data in a textbox.text property. The next time something was written to the textbox the original data would be gone. At least if it is in a string variable it is protected from things outside the sub. Maybe I'm just overcautious but it doesn't seem like too much extra to protect the data.

[bwquestion]

Thanks again .paul. This gives me a good understanding.