TextBox Text Changed Event : TextBox « GUI « VB.Net Tutorial

1. VB.Net Tutorial
2. GUI
3. TextBox

imports System
imports System.Drawing
imports System.Windows.Forms

public class TextBoxTextChanged : inherits Form

  dim txt as TextBox
  dim btn as Button
  dim strOriginal as string

  public sub New()
        Text = "TextBox Modified and TextChanged"
    Size = new Size(300, 375)

    txt = new TextBox()
    txt.Parent = me
    txt.Text = "Enter text here."
    txt.Size = new Size(280, 275)
    txt.Location = new Point(10,10)
    AddHandler txt.TextChanged, AddressOf txt_TextChanged
    txt.Multiline = true
    txt.BorderStyle = BorderStyle.Fixed3D
    txt.ScrollBars = ScrollBars.Vertical
    txt.Anchor = AnchorStyles.Left or AnchorStyles.Right or AnchorStyles.Top or AnchorStyles.Bottom
    strOriginal = txt.Text

    btn = new Button()
    btn.Parent = me
    btn.Text = "Check "
    btn.Location = new Point(20,320)
    AddHandler btn.Click, AddressOf btn_Click
    btn.Anchor = AnchorStyles.Bottom

  end sub

  public shared sub Main() 
    Application.Run(new TextBoxTextChanged())
  end sub

  private sub txt_TextChanged(ByVal sender as object,ByVal e as EventArgs)
    Console.WriteLine("txt_TextChanged")
    if strOriginal = txt.Text then
      txt.Modified = false
    else
      txt.Modified = true
    end if
  end sub

  private sub btn_Click(ByVal sender as object,ByVal e as EventArgs)
    if txt.Modified then
      Console.WriteLine("modified.")
      strOriginal = txt.Text
      txt.Modified = false
    else
      Console.WriteLine("not been modified." )
    end if
  end sub
end class

14.23.TextBox
	14.23.1.	Get input from TextBox and Set to Label
	14.23.2.	Convert input value in a TextField
	14.23.3.	Inherit TextBox to create custom control based on TextBox
	14.23.4.	Display text file in a TextBox
	14.23.5.	Numeric TextBox
	14.23.6.	TextBox Text Changed Event
	14.23.7.	Comprehensive Demo for TextBox
	14.23.8.	Change TextBox font by RadioButton and CheckBox
	14.23.9.	Get selected text in TextBox
	14.23.10.	Create PasswordField by setting the TextBox.PasswordChar
	14.23.11.	Copy selection text from a TextBox and paste to another
	14.23.12.	Multiline Text Boxes
	14.23.13.	Disable TextBox Context Menu
	14.23.14.	Save text in TextBox to a file
	14.23.15.	Handles the Click event of a Button to change the background color of a TextBox.