AutoValidate 枚举
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
确定控件在失去用户输入焦点时应如何验证其数据。
public enum class AutoValidate
public enum AutoValidate
type AutoValidate =
Public Enum AutoValidate
- 继承
字段
Disable | 0 | 将不进行隐式验证。 设置此值将不会妨碍对 Validate() 或 ValidateChildren() 的显式调用。 |
EnableAllowFocusChange | 2 | 发生隐式验证,但如果验证失败,焦点仍将更改到新控件。 如果验证失败,将不激发 Validated 事件。 |
EnablePreventFocusChange | 1 | 当控件失去焦点时发生隐式验证。 |
Inherit | -1 | 控件从其容器(如窗体或其他控件)中继承它的 AutoValidate 行为。 如果没有容器控件,则它默认为 EnablePreventFocusChange。 |
示例
下面的代码示例关闭窗体及其包含的所有控件的隐式验证,而是在单击鼠标按钮时手动执行窗体的所有子项的验证。
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
注解
如果用户关闭Windows 窗体控件的焦点,该控件将使用 AutoValidate 来确定如何验证其数据。 这种类型的验证称为隐式验证,因为它发生时,应用程序开发人员无需显式调用 Validate 或 ValidateChildren。
对应于此值的属性将具有不同的默认值,具体取决于控件的类型。 有关详细信息,请参阅 Windows 窗体 中的用户输入验证。