Is there an option for changing boolean variables trough a loop in vb.net

Question

I am trying to change different values in a for loop in vb.net. However, I couldn't find how to change the numbered boolean variables.

Dim txt1 As Boolean = False
Dim txt2 As Boolean = False
 i = i + 1
            If i < 9 Then
                'I tried to do:
                Me.Controls("txt" & i.ToString) = True
                txt(i) = True
            End If

How can I change the numbered boolean variables and what is the most efficient way to it?

If you enable [`Option Strict On`](https://stackoverflow.com/a/29985039/1115360) for the current project then Visual Studio will guide you to where corrections are needed. What is the type of the *controls* `txt1` and `txt2`? You can't have variables with the same names as controls because the controls are referenced by variables with those names. — Andrew Morton, Mar 02 '20 at 12:35
Why would you think that you could access a `Boolean` variable via the `Controls` collection of the form? Are they controls? You can access a control on the form from the `Controls` collection by providing the `Name` property value of the control. It's got nothing to do with variables. If you add a control in the designer then the variable used to refer to it has the same name as its `Name` property but that is just a convenience. They don't have to be the same and won't be if you add controls at run time. `Boolean` values aren't controls and don't have a `Name` property. — jmcilhinney, Mar 02 '20 at 13:09
The right way to do what I think you're trying to do is to use an array or a `List` rather than individual variables. You can't access variables by a dynamically-constructed name except by using slow (and ugly) reflection-based approaches. — Craig, Mar 02 '20 at 14:47
Maybe you want to add your bool values to a `List(Of Boolean)`. Then use the index to change values in the List. — Jimi, Mar 02 '20 at 14:48
Pretty hard to visualize the practicality of a `List(Of Boolean)`. `Dictionary(Of String, Boolean)` would be something useful. You really should share more information about your intent. — LarsTech, Mar 02 '20 at 15:27

score 1 · Accepted Answer · answered Mar 03 '20 at 10:02

1

The right way to access the booleans is in an array or a list.

Using the example of the question:

Dim bool(2) As Boolean

i = i + 1
        If i < 9 Then
            bool(i) = True
        End If

answered Mar 03 '20 at 10:02

Klaas Weerstand

77
11

score 0 · Answer 2 · answered Mar 12 '20 at 22:34

I guess you want to iterate over the TextBox controls and then change the property of TextBox.enabled.

You can try the following methods.

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    For Each c As Control In Me.Controls
        If c.GetType.ToString() = "System.Windows.Forms.TextBox" Then
            c.Enabled = True 'You can change the TextBox Controls. Enabled to False too.
            c.Text = c.Name.ToString
        End If
    Next
End Sub

Is there an option for changing boolean variables trough a loop in vb.net

2 Answers2