AutoValidate Enum

Definition

public enum class AutoValidate

public enum AutoValidate

type AutoValidate = 

Public Enum AutoValidate

Inheritance

Object

ValueType

Enum

AutoValidate

Fields

Examples

The following code example turns off implicit validation for a form and all of its contained controls, and instead manually performs validation of all of the form's children when a mouse button is clicked.

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Drawing;
using System.Text;

namespace TestValidation
{
 class Form1 : Form
 {
 private static void Main(string[] args)
 {
 Application.EnableVisualStyles();
 Application.Run(new Form1());
 }

 private TextBox firstNameBox, lastNameBox;
 private Button validateButton;
 private FlowLayoutPanel flowLayout1;

 private Form1()
 {
 this.Load += new EventHandler(Form1_Load);
 }

 void Form1_Load(object sender, EventArgs e)
 {
 // Turn off validation when a control loses focus. This will be inherited by child
 // controls on the form, enabling us to validate the entire form when the 
 // button is clicked instead of one control at a time.
 this.AutoValidate = AutoValidate.Disable;

 flowLayout1 = new FlowLayoutPanel();
 flowLayout1.Dock = DockStyle.Fill;
 flowLayout1.Name = "flowLayout1";

 firstNameBox = new TextBox();
 firstNameBox.Name = "firstNameBox";
 firstNameBox.Size = new Size(75, firstNameBox.Size.Height);
 firstNameBox.CausesValidation = true;
 firstNameBox.Validating += new System.ComponentModel.CancelEventHandler(firstNameBox_Validating);
 flowLayout1.Controls.Add(firstNameBox);

 lastNameBox = new TextBox();
 lastNameBox.Name = "lastNameBox";
 lastNameBox.Size = new Size(75, lastNameBox.Size.Height);
 lastNameBox.CausesValidation = true;
 lastNameBox.Validating += new System.ComponentModel.CancelEventHandler(lastNameBox_Validating);
 flowLayout1.Controls.Add(lastNameBox);

 validateButton = new Button();
 validateButton.Text = "Validate";
 // validateButton.Location = new Point(170, 10);
 validateButton.Size = new Size(75, validateButton.Size.Height);
 validateButton.Click += new EventHandler(validateButton_Click);
 flowLayout1.Controls.Add(validateButton);

 this.Controls.Add(flowLayout1);

 this.Text = "Test Validation";
 }

 void firstNameBox_Validating(object sender, System.ComponentModel.CancelEventArgs e)
 {
 if (firstNameBox.Text.Length == 0)
 {
 e.Cancel = true;
 }
 else
 {
 e.Cancel = false;
 }
 }

 void lastNameBox_Validating(object sender, System.ComponentModel.CancelEventArgs e)
 {
 e.Cancel = false;
 }

 void validateButton_Click(object sender, EventArgs e)
 {
 if (this.ValidateChildren())
 {
 MessageBox.Show("Validation succeeded!");
 }
 else
 {
 MessageBox.Show("Validation failed.");
 }
 }
 }
}

Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1
 Inherits Form

 'Entry point which delegates to C-style main Private Function
 Public Overloads Shared Sub Main()
 Main(System.Environment.GetCommandLineArgs())
 End Sub

 Private Overloads Shared Sub Main(ByVal args() As String)
 Application.EnableVisualStyles()
 Application.Run(New Form1())
 End Sub

 Private WithEvents FirstNameBox, LastNameBox As TextBox
 Private WithEvents ValidateButton As Button
 Private FlowLayout1 As FlowLayoutPanel

 Private Sub New()
 End Sub

 Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
 ' Turn off validation when a control loses focus. This will be inherited by child
 ' controls on the form, enabling us to validate the entire form when the 
 ' button is clicked instead of one control at a time.
 Me.AutoValidate = System.Windows.Forms.AutoValidate.Disable

 FlowLayout1 = New FlowLayoutPanel()
 FlowLayout1.Dock = DockStyle.Fill

 FirstNameBox = New TextBox()
 FirstNameBox.Name = "FirstNameBox"
 FirstNameBox.Location = New Point(10, 10)
 FirstNameBox.Size = New Size(75, FirstNameBox.Size.Height)
 FirstNameBox.CausesValidation = True
 FlowLayout1.Controls.Add(FirstNameBox)

 LastNameBox = New TextBox()
 LastNameBox.Name = "LastNameBox"
 LastNameBox.Location = New Point(90, 10)
 LastNameBox.Size = New Size(75, LastNameBox.Size.Height)
 LastNameBox.CausesValidation = True
 FlowLayout1.Controls.Add(LastNameBox)

 ValidateButton = New Button()
 ValidateButton.Text = "Validate"
 ValidateButton.Location = New Point(170, 10)
 ValidateButton.Size = New Size(75, ValidateButton.Size.Height)
 FlowLayout1.Controls.Add(ValidateButton)

 Me.Text = "Test Validation"

 Me.Controls.Add(FlowLayout1)
 End Sub


 Private Sub FirstNameBox_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles FirstNameBox.Validating
 If FirstNameBox.Text.Length = 0 Then
 e.Cancel = True
 Else
 e.Cancel = False
 End If
 End Sub


 Private Sub LastNameBox_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles LastNameBox.Validating
 e.Cancel = False
 End Sub


 Private Sub ValidateButton_Click(ByVal sender As Object, ByVal e As EventArgs) Handles ValidateButton.Click
 If ValidateChildren() Then
 MessageBox.Show("Validation succeeded!")
 Else
 MessageBox.Show("Validation failed.")
 End If
 End Sub
End Class

Remarks

If a user switches focus off of a Windows Forms control, the control will use AutoValidate to determine how to validate its data. This type of validation is called implicit validation, because it occurs without the application developer having to make an explicit call to Validate or ValidateChildren.

The property corresponding to this value will have different defaults based on the type of control. For more information, see User Input Validation in Windows Forms.

See also

• ValidateChildren()
• AutoValidate