How to put many Textbox in one If else statement - vb.net

Question

This is the question
=If the FN button
will be click, then it will display a message base on the status of the textbox1 control. For the MN button, if
the event is click then it will display a message base on the status of the textbox2 control. The LN button
was clicked then it will display a message base on the status of the textbox3 control. Lastly, if the Clear
button control will be click and any of the textbox control is not empty then it will clear all the textbox
controls, but if all textbox controls are empty then it will show a message that all textbox controls are empty.
this is my code
Public Class Form1
Private Sub Label1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label1.Click
Label1.Text = "First Name"
End Sub
Private Sub Label2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label2.Click
Label2.Text = "Middle Name"
End Sub
Private Sub Label3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label3.Click
Label3.Text = "Last Name"
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Button1.Text = "FN"
If TextBox1.Text = vbNullString Then
MessageBox.Show("The First name is empty")
Else MessageBox.Show("The First name is " & TextBox1.Text)
End If
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Button2.Text = "MN"
If TextBox2.Text = vbNullString Then
MessageBox.Show("The Middle name is empty")
Else : MessageBox.Show("The Middle name is " & TextBox2.Text)
End If
End Sub
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Button3.Text = "LN"
If TextBox3.Text = vbNullString Then
MessageBox.Show("The Last name is empty")
Else : MessageBox.Show("The Last name is " & TextBox3.Text)
End If
End Sub
Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
Button4.Text = "Clear"
If (TextBox1.Text) And (TextBox2.Text) = vbNullString Then
MessageBox.Show("Textbox control is empty")
Else : TextBox1.Clear()
End If
For Each txt As Control In Me.Controls.OfType(Of TextBox)()
txt.Text = ""
Next
End Sub
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
End Sub
Private Sub TextBox2_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox2.TextChanged
End Sub
End Class
My question is , how to work on clear button because i cant do it in Textbox2 and Textbox3 thankyou

Answer 1

Try something like this
For Each ctrl As Control In Me.Controls
If TypeOf ctrl Is TextBox Then
CType(ctrl, TextBox).Text = String.Empty
End If
Next ctrl
Try to add Next txt to your For Each

Answer 2

So, you are asking about Button4_Click.
This is what I was about to suggest first, because clearing all text boxes whether they are empty or not, is faster than first checking and then clearing.
Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
' Button4.Text = "Clear"
' If (TextBox1.Text) And (TextBox2.Text) = vbNullString Then
' MessageBox.Show("Textbox control is empty")
' Else : TextBox1.Clear()
' End If
For Each txt As Control In Me.Controls.OfType(Of TextBox)()
txt.Text = ""
Next
MessageBox.Show("Textbox controls are empty")
End Sub
But then, if the intention is to a) just clear all textboxes, without any message if any one has some text. b) show the message only if all are empty.
Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
' Button4.Text = "Clear"
If (TextBox1.Text = vbNullString) And (TextBox2.Text = vbNullString) And (TextBox3.Text = vbNullString) Then
MessageBox.Show("Textbox controls are empty")
Else
TextBox1.Text = ""
TextBox2.Text = ""
TextBox3.Text = ""
End If
or (if this works, VB6 is alien for me)
....
Else
For Each txt As Control In Me.Controls.OfType(Of TextBox)()
txt.Text = ""
Next
End If
End Sub

Answer 3

I'd use a List(Of TextBox) allowing you to leverage All and ForEach:
Public Class Form1
Private TBs As New List(Of TextBox)
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
TBs.AddRange({TextBox1, TextBox2, TextBox3})
End Sub
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
If TBs.All(Function(tb) tb.Text = "") Then
MessageBox.Show("All TextBoxes are empty!")
Else
TBs.ForEach(Sub(tb) tb.Clear())
End If
End Sub
End Class

Answer 4

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
' Button4.Text = "Clear"
If (TextBox1.Text = vbNullString) And (TextBox2.Text = vbNullString) And (TextBox3.Text = vbNullString) Then
MessageBox.Show("Textbox controls are empty")
Else
TextBox1.Text = ""
TextBox2.Text = ""
TextBox3.Text = ""
End If
thanks sir Tom Brunberg, this code works for me :)