Question

I need to take the first 5 characters so they match back up with the picturebox I saved early with the same name.

This filename as an example could be 12345_Text_Text_Text.pdf

Dim key As String = Path.GetFileNameWithoutExtension(e.Name)
Dim p As PictureBox = CType(Me.Controls(key), PictureBox)
p.Image = My.Resources.Ok

I thought doing this would’ve worked;

Dim subkey As String
Dim key As String = Path.GetFileNameWithoutExtension(e.Name)
subkey = Left(key, 5)

The problem seems to the Left command, Public Property Left As Integer' has no parameters and its return type cannot be indexed.

Full sub routine here;

    Private Sub Watcher_Changed(ByVal sender As Object, ByVal e As FileSystemEventArgs) Handles Watcher.Changed

    Dim key As String = Path.GetFileNameWithoutExtension(e.Name)

    Dim subkey As String
    subkey = Left(key, 5)

    Dim p As PictureBox = CType(Me.Controls(key), PictureBox)
    p.Image = My.Resources.Ok

    End Sub

Suggestions on what I’m doing wrong?

Answer 1

Change your call to to the following:

subkey = Strings.Left(key,5);

Left is a static method attached to instances of the Strings object, so your problem was just one of notation (standalone Left reference).

Hope this helps fix the problem.

EDIT for clarification/demonstration:

As noted by @SSS below, Forms in WinForms projects have a Left property that defines the horizontal position of the form on the screen. When the “Left” method was called without qualification, eg no object or namespace reference preceding it, VB went to its resolution process to determine how to interpret it. That native “Left” property of the form was the “winner,” but with the arguments provided caused the error you received.

To resolve name conflicts like this, the solution is to provide what’s called a fully qualified reference to the method or property in question. Supplying “Microsoft.VisualBasic.Left” is a perfectly valid way of resolving this, as is supplying the reference to the Strings class as noted here.

I hope this helps clear up any confusion.

As there may be some minor uncertainty or confusion on this suggested fix, here are some screenshots of it being used in a test project:

Sample code using Strings.Left in VB.NET…

Result from sample code