AutoValidate 列舉
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
在控制項失去使用者輸入焦點時,決定控制項如何驗證其資料。
public enum class AutoValidate
public enum AutoValidate
type AutoValidate =
Public Enum AutoValidate
- 繼承
欄位
Disable | 0 | 隱含驗證不會發生。 設定這個值不會干預明確呼叫 Validate() 或 ValidateChildren()。 |
EnableAllowFocusChange | 2 | 隱含驗證會發生,但如果驗證失敗,焦點還是會變更為新控制項。 如果驗證失敗,將不會引發 Validated 事件。 |
EnablePreventFocusChange | 1 | 隱含驗證發生於控制項失去焦點時。 |
Inherit | -1 | 控制項自其容器繼承其 AutoValidate 行為 (例如,表單或其他控制項)。 如果沒有容器控制項,則預設值為 EnablePreventFocusChange。 |
範例
下列程式碼範例會關閉表單及其所有自主控制項的隱含驗證,而是在按一下滑鼠按鍵時手動執行所有表單子系的驗證。
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
備註
如果使用者關閉Windows Forms控制項的焦點,控制項會用來 AutoValidate 判斷如何驗證其資料。 這種類型的驗證稱為隱含驗證,因為它在沒有應用程式開發人員必須明確呼叫 Validate 或 ValidateChildren 的情況下發生。
對應至此值的屬性會根據控制項的類型,有不同的預設值。 如需詳細資訊,請參閱Windows Forms 中的使用者輸入驗證。