AutoValidate Enum

Definition

public enum class AutoValidate

public enum AutoValidate

type AutoValidate = 

Public Enum AutoValidate

Arv

Object

ValueType

Enum

AutoValidate

Fält

Exempel

I följande kodexempel inaktiveras implicit validering för ett formulär och alla dess inneslutna kontroller och utför i stället validering manuellt av alla formulärs underordnade objekt när en musknapp klickas.

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

Kommentarer

Om en användare växlar fokus från en Windows Forms kontroll använder kontrollen AutoValidate för att fastställa hur data ska verifieras. Den här typen av validering kallas implicit validering eftersom den sker utan att programutvecklaren behöver göra ett explicit anrop till Validate eller ValidateChildren.

Egenskapen som motsvarar det här värdet har olika standardvärden baserat på typen av kontroll. Mer information finns i Användarverifiering av indata i Windows Forms.

Se även

• ValidateChildren()
• AutoValidate