ErrorProvider.SetError 方法
设置指定控件的错误描述字符串。
**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms（在 system.windows.forms.dll 中）
语法
声明
Public Sub SetError ( _
control As Control, _
value As String _
)
用法
Dim instance As ErrorProvider
Dim control As Control
Dim value As String
instance.SetError(control, value)
public void SetError (
Control control,
string value
)
public:
void SetError (
Control^ control,
String^ value
)
public void SetError (
Control control,
String value
)
public function SetError (
control : Control,
value : String
)
参数
- control
要为其设置错误描述字符串的控件。
- value
错误描述字符串。
异常
| 异常类型 | 条件 |
|---|---|
control 为 空引用（在 Visual Basic 中为 Nothing）。 |
备注
如果字符串长度大于零，则显示错误图标，而错误图标的“工具提示”是错误描述文本。如果字符串长度为零，则隐藏错误图标。
示例
下面的代码示例演示使用 ErrorProvider 类来通知用户有数据输入错误。该示例创建了一个包含 TextBox 控件、NumericUpDown 控件和 ComboBox 控件的 Form，并为每个控件创建 ErrorProvider，这些控件验证各自的内容。该示例使用 BlinkRate 和 BlinkStyle 属性及 SetIconAlignment 和 SetIconPadding 方法来设置错误图标选项。在控件的 Validated 事件过程中是否使用适当的错误文本调用 SetError 方法，取决于控件的内容。
Imports System
Imports System.Drawing
Imports System.Windows.Forms
Namespace ErrorProvider
Public NotInheritable Class Form1
Inherits System.Windows.Forms.Form
Private label1 As System.Windows.Forms.Label
Private label2 As System.Windows.Forms.Label
Private label3 As System.Windows.Forms.Label
Private label4 As System.Windows.Forms.Label
Private label5 As System.Windows.Forms.Label
Private label6 As System.Windows.Forms.Label
Friend WithEvents favoriteColorComboBox As System.Windows.Forms.ComboBox
Friend WithEvents nameTextBox1 As System.Windows.Forms.TextBox
Friend WithEvents ageUpDownPicker As System.Windows.Forms.NumericUpDown
Private ageErrorProvider As System.Windows.Forms.ErrorProvider
Private nameErrorProvider As System.Windows.Forms.ErrorProvider
Private favoriteColorErrorProvider As System.Windows.Forms.ErrorProvider
<System.STAThread()> _
Public Shared Sub Main()
System.Windows.Forms.Application.Run(New Form1())
End Sub 'Main
Public Sub New()
Me.nameTextBox1 = New System.Windows.Forms.TextBox()
Me.label1 = New System.Windows.Forms.Label()
Me.label2 = New System.Windows.Forms.Label()
Me.ageUpDownPicker = New System.Windows.Forms.NumericUpDown()
Me.favoriteColorComboBox = New System.Windows.Forms.ComboBox()
Me.label3 = New System.Windows.Forms.Label()
Me.label4 = New System.Windows.Forms.Label()
Me.label5 = New System.Windows.Forms.Label()
Me.label6 = New System.Windows.Forms.Label()
' Name Label
Me.label1.Location = New System.Drawing.Point(56, 32)
Me.label1.Size = New System.Drawing.Size(40, 23)
Me.label1.Text = "Name:"
' Age Label
Me.label2.Location = New System.Drawing.Point(40, 64)
Me.label2.Size = New System.Drawing.Size(56, 23)
Me.label2.Text = "Age (3-5)"
' Favorite Color Label
Me.label3.Location = New System.Drawing.Point(24, 96)
Me.label3.Size = New System.Drawing.Size(80, 24)
Me.label3.Text = "Favorite color"
' ErrorBlinkStyle.AlwaysBlink Label
Me.label4.Location = New System.Drawing.Point(264, 32)
Me.label4.Size = New System.Drawing.Size(160, 23)
Me.label4.Text = "ErrorBlinkStyle.AlwaysBlink"
' ErrorBlinkStyle.BlinkIfDifferentError Label
Me.label5.Location = New System.Drawing.Point(264, 64)
Me.label5.Size = New System.Drawing.Size(200, 23)
Me.label5.Text = "ErrorBlinkStyle.BlinkIfDifferentError"
' ErrorBlinkStyle.NeverBlink Label
Me.label6.Location = New System.Drawing.Point(264, 96)
Me.label6.Size = New System.Drawing.Size(200, 23)
Me.label6.Text = "ErrorBlinkStyle.NeverBlink"
' Name TextBox
Me.nameTextBox1.Location = New System.Drawing.Point(112, 32)
Me.nameTextBox1.Size = New System.Drawing.Size(120, 20)
Me.nameTextBox1.TabIndex = 0
' Age NumericUpDown
Me.ageUpDownPicker.Location = New System.Drawing.Point(112, 64)
Me.ageUpDownPicker.Maximum = New System.Decimal(New Integer() {150, 0, 0, 0})
Me.ageUpDownPicker.TabIndex = 4
' Favorite Color ComboBox
Me.favoriteColorComboBox.Items.AddRange(New Object() {"None", "Red", "Yellow", _
"Green", "Blue", "Purple"})
Me.favoriteColorComboBox.Location = New System.Drawing.Point(112, 96)
Me.favoriteColorComboBox.Size = New System.Drawing.Size(120, 21)
Me.favoriteColorComboBox.TabIndex = 5
' Set up how the form should be displayed and add the controls to the form.
Me.ClientSize = New System.Drawing.Size(464, 150)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.label6, Me.label5, Me.label4, _
Me.label3, Me.favoriteColorComboBox, Me.ageUpDownPicker, Me.label2, _
Me.label1, Me.nameTextBox1})
Me.Text = "Error Provider Example"
' Create and set the ErrorProvider for each data entry control.
nameErrorProvider = New System.Windows.Forms.ErrorProvider()
nameErrorProvider.SetIconAlignment(Me.nameTextBox1, ErrorIconAlignment.MiddleRight)
nameErrorProvider.SetIconPadding(Me.nameTextBox1, 2)
nameErrorProvider.BlinkRate = 1000
nameErrorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.AlwaysBlink
ageErrorProvider = New System.Windows.Forms.ErrorProvider()
ageErrorProvider.SetIconAlignment(Me.ageUpDownPicker, ErrorIconAlignment.MiddleRight)
ageErrorProvider.SetIconPadding(Me.ageUpDownPicker, 2)
ageErrorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.BlinkIfDifferentError
favoriteColorErrorProvider = New System.Windows.Forms.ErrorProvider()
favoriteColorErrorProvider.SetIconAlignment(Me.favoriteColorComboBox, ErrorIconAlignment.MiddleRight)
favoriteColorErrorProvider.SetIconPadding(Me.favoriteColorComboBox, 2)
favoriteColorErrorProvider.BlinkRate = 1000
favoriteColorErrorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.NeverBlink
End Sub 'New
Private Sub nameTextBox1_Validated(sender As Object, e As System.EventArgs) Handles nameTextBox1.Validated
If IsNameValid() Then
' Clear the error, if any, in the error provider.
nameErrorProvider.SetError(Me.nameTextBox1, "")
Else
' Set the error if the name is not valid.
nameErrorProvider.SetError(Me.nameTextBox1, "Name is required.")
End If
End Sub
Private Sub ageUpDownPicker_Validated(sender As Object, e As System.EventArgs) Handles ageUpDownPicker.Validated
If IsAgeTooYoung() Then
' Set the error if the age is too young.
ageErrorProvider.SetError(Me.ageUpDownPicker, "Age not old enough")
ElseIf IsAgeTooOld() Then
' Set the error if the age is too old.
ageErrorProvider.SetError(Me.ageUpDownPicker, "Age is too old")
Else
' Clear the error, if any, in the error provider.
ageErrorProvider.SetError(Me.ageUpDownPicker, "")
End If
End Sub
Private Sub favoriteColorComboBox_Validated(sender As Object, e As System.EventArgs) Handles favoriteColorComboBox.Validated
If Not IsColorValid() Then
' Set the error if the favorite color is not valid.
favoriteColorErrorProvider.SetError(Me.favoriteColorComboBox, "Must select a color.")
Else
' Clear the error, if any, in the error provider.
favoriteColorErrorProvider.SetError(Me.favoriteColorComboBox, "")
End If
End Sub
' Functions to verify data.
Private Function IsNameValid() As Boolean
' Determine whether the text box contains a zero-length string.
Return nameTextBox1.Text.Length > 0
End Function
Private Function IsAgeTooYoung() As Boolean
' Determine whether the age value is less than three.
Return ageUpDownPicker.Value < 3
End Function
Private Function IsAgeTooOld() As Boolean
' Determine whether the age value is greater than five.
Return ageUpDownPicker.Value > 5
End Function
Private Function IsColorValid() As Boolean
' Determine whether the favorite color has a valid value.
If Not (favoriteColorComboBox.SelectedItem Is Nothing) Then
If Not(favoriteColorComboBox.SelectedItem.ToString().Equals("None")) Then
Return true
End If
End If
Return false
End Function
End Class 'Form1
End Namespace 'ErrorProvider
using System;
using System.Drawing;
using System.Windows.Forms;
namespace ErrorProvider
{
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Label label4;
private System.Windows.Forms.Label label5;
private System.Windows.Forms.Label label6;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.TextBox nameTextBox1;
private System.Windows.Forms.NumericUpDown ageUpDownPicker;
private System.Windows.Forms.ComboBox favoriteColorComboBox;
private System.Windows.Forms.ErrorProvider ageErrorProvider;
private System.Windows.Forms.ErrorProvider nameErrorProvider;
private System.Windows.Forms.ErrorProvider favoriteColorErrorProvider;
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
public Form1()
{
this.nameTextBox1 = new System.Windows.Forms.TextBox();
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.ageUpDownPicker = new System.Windows.Forms.NumericUpDown();
this.favoriteColorComboBox = new System.Windows.Forms.ComboBox();
this.label3 = new System.Windows.Forms.Label();
this.label4 = new System.Windows.Forms.Label();
this.label5 = new System.Windows.Forms.Label();
this.label6 = new System.Windows.Forms.Label();
// Name Label
this.label1.Location = new System.Drawing.Point(56, 32);
this.label1.Size = new System.Drawing.Size(40, 23);
this.label1.Text = "Name:";
// Age Label
this.label2.Location = new System.Drawing.Point(40, 64);
this.label2.Size = new System.Drawing.Size(56, 23);
this.label2.Text = "Age (3-5)";
// Favorite Color Label
this.label3.Location = new System.Drawing.Point(24, 96);
this.label3.Size = new System.Drawing.Size(80, 24);
this.label3.Text = "Favorite color";
// ErrorBlinkStyle.AlwaysBlink Label
this.label4.Location = new System.Drawing.Point(264, 32);
this.label4.Size = new System.Drawing.Size(160, 23);
this.label4.Text = "ErrorBlinkStyle.AlwaysBlink";
// ErrorBlinkStyle.BlinkIfDifferentError Label
this.label5.Location = new System.Drawing.Point(264, 64);
this.label5.Size = new System.Drawing.Size(200, 23);
this.label5.Text = "ErrorBlinkStyle.BlinkIfDifferentError";
// ErrorBlinkStyle.NeverBlink Label
this.label6.Location = new System.Drawing.Point(264, 96);
this.label6.Size = new System.Drawing.Size(200, 23);
this.label6.Text = "ErrorBlinkStyle.NeverBlink";
// Name TextBox
this.nameTextBox1.Location = new System.Drawing.Point(112, 32);
this.nameTextBox1.Size = new System.Drawing.Size(120, 20);
this.nameTextBox1.TabIndex = 0;
this.nameTextBox1.Validated += new System.EventHandler(this.nameTextBox1_Validated);
// Age NumericUpDown
this.ageUpDownPicker.Location = new System.Drawing.Point(112, 64);
this.ageUpDownPicker.Maximum = new System.Decimal(new int[] {150,0,0,0});
this.ageUpDownPicker.TabIndex = 4;
this.ageUpDownPicker.Validated += new System.EventHandler(this.ageUpDownPicker_Validated);
// Favorite Color ComboBox
this.favoriteColorComboBox.Items.AddRange(new object[] {"None","Red","Yellow",
"Green","Blue","Purple"});
this.favoriteColorComboBox.Location = new System.Drawing.Point(112, 96);
this.favoriteColorComboBox.Size = new System.Drawing.Size(120, 21);
this.favoriteColorComboBox.TabIndex = 5;
this.favoriteColorComboBox.Validated += new System.EventHandler(this.favoriteColorComboBox_Validated);
// Set up how the form should be displayed and add the controls to the form.
this.ClientSize = new System.Drawing.Size(464, 150);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
this.label6,this.label5,this.label4,this.label3,
this.favoriteColorComboBox,this.ageUpDownPicker,
this.label2,this.label1,this.nameTextBox1});
this.Text = "Error Provider Example";
// Create and set the ErrorProvider for each data entry control.
nameErrorProvider = new System.Windows.Forms.ErrorProvider();
nameErrorProvider.SetIconAlignment (this.nameTextBox1, ErrorIconAlignment.MiddleRight);
nameErrorProvider.SetIconPadding (this.nameTextBox1, 2);
nameErrorProvider.BlinkRate = 1000;
nameErrorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.AlwaysBlink;
ageErrorProvider = new System.Windows.Forms.ErrorProvider();
ageErrorProvider.SetIconAlignment (this.ageUpDownPicker, ErrorIconAlignment.MiddleRight);
ageErrorProvider.SetIconPadding (this.ageUpDownPicker, 2);
ageErrorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.BlinkIfDifferentError;
favoriteColorErrorProvider = new System.Windows.Forms.ErrorProvider();
favoriteColorErrorProvider.SetIconAlignment (this.favoriteColorComboBox, ErrorIconAlignment.MiddleRight);
favoriteColorErrorProvider.SetIconPadding (this.favoriteColorComboBox, 2);
favoriteColorErrorProvider.BlinkRate = 1000;
favoriteColorErrorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.NeverBlink;
}
private void nameTextBox1_Validated(object sender, System.EventArgs e)
{
if(IsNameValid())
{
// Clear the error, if any, in the error provider.
nameErrorProvider.SetError(this.nameTextBox1, "");
}
else
{
// Set the error if the name is not valid.
nameErrorProvider.SetError(this.nameTextBox1, "Name is required.");
}
}
private void ageUpDownPicker_Validated(object sender, System.EventArgs e)
{
if (IsAgeTooYoung())
{
// Set the error if the age is too young.
ageErrorProvider.SetError(this.ageUpDownPicker, "Age not old enough");
}
else if (IsAgeTooOld())
{
// Set the error if the age is too old.
ageErrorProvider.SetError(this.ageUpDownPicker, "Age is too old");
}
else
{
// Clear the error, if any, in the error provider.
ageErrorProvider.SetError(this.ageUpDownPicker, "");
}
}
private void favoriteColorComboBox_Validated(object sender, System.EventArgs e)
{
if (!IsColorValid())
{
// Set the error if the favorite color is not valid.
favoriteColorErrorProvider.SetError(this.favoriteColorComboBox, "Must select a color.");
}
else
{
// Clear the error, if any, in the error provider.
favoriteColorErrorProvider.SetError(this.favoriteColorComboBox, "");
}
}
// Functions to verify data.
private bool IsNameValid()
{
// Determine whether the text box contains a zero-length string.
return (nameTextBox1.Text.Length > 0);
}
private bool IsAgeTooYoung()
{
// Determine whether the age value is less than three.
return (ageUpDownPicker.Value < 3);
}
private bool IsAgeTooOld()
{
// Determine whether the age value is greater than five.
return (ageUpDownPicker.Value > 5 );
}
private bool IsColorValid()
{
// Determine whether the favorite color has a valid value.
return ((favoriteColorComboBox.SelectedItem != null) &&
(!favoriteColorComboBox.SelectedItem.ToString().Equals("None")));
}
}
}
#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>
using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
public ref class Form1: public System::Windows::Forms::Form
{
private:
System::Windows::Forms::Label ^ label1;
System::Windows::Forms::Label ^ label2;
System::Windows::Forms::Label ^ label4;
System::Windows::Forms::Label ^ label5;
System::Windows::Forms::Label ^ label6;
System::Windows::Forms::Label ^ label3;
System::Windows::Forms::TextBox^ nameTextBox1;
System::Windows::Forms::NumericUpDown^ ageUpDownPicker;
System::Windows::Forms::ComboBox^ favoriteColorComboBox;
System::Windows::Forms::ErrorProvider^ ageErrorProvider;
System::Windows::Forms::ErrorProvider^ nameErrorProvider;
System::Windows::Forms::ErrorProvider^ favoriteColorErrorProvider;
public:
Form1()
{
this->nameTextBox1 = gcnew System::Windows::Forms::TextBox;
this->label1 = gcnew System::Windows::Forms::Label;
this->label2 = gcnew System::Windows::Forms::Label;
this->ageUpDownPicker = gcnew System::Windows::Forms::NumericUpDown;
this->favoriteColorComboBox = gcnew System::Windows::Forms::ComboBox;
this->label3 = gcnew System::Windows::Forms::Label;
this->label4 = gcnew System::Windows::Forms::Label;
this->label5 = gcnew System::Windows::Forms::Label;
this->label6 = gcnew System::Windows::Forms::Label;
// Name Label
this->label1->Location = System::Drawing::Point( 56, 32 );
this->label1->Size = System::Drawing::Size( 40, 23 );
this->label1->Text = "Name:";
// Age Label
this->label2->Location = System::Drawing::Point( 40, 64 );
this->label2->Size = System::Drawing::Size( 56, 23 );
this->label2->Text = "Age (3-5)";
// Favorite Color Label
this->label3->Location = System::Drawing::Point( 24, 96 );
this->label3->Size = System::Drawing::Size( 80, 24 );
this->label3->Text = "Favorite color";
// ErrorBlinkStyle::AlwaysBlink Label
this->label4->Location = System::Drawing::Point( 264, 32 );
this->label4->Size = System::Drawing::Size( 160, 23 );
this->label4->Text = "ErrorBlinkStyle::AlwaysBlink";
// ErrorBlinkStyle::BlinkIfDifferentError Label
this->label5->Location = System::Drawing::Point( 264, 64 );
this->label5->Size = System::Drawing::Size( 200, 23 );
this->label5->Text = "ErrorBlinkStyle::BlinkIfDifferentError";
// ErrorBlinkStyle::NeverBlink Label
this->label6->Location = System::Drawing::Point( 264, 96 );
this->label6->Size = System::Drawing::Size( 200, 23 );
this->label6->Text = "ErrorBlinkStyle::NeverBlink";
// Name TextBox
this->nameTextBox1->Location = System::Drawing::Point( 112, 32 );
this->nameTextBox1->Size = System::Drawing::Size( 120, 20 );
this->nameTextBox1->TabIndex = 0;
this->nameTextBox1->Validated += gcnew System::EventHandler( this, &Form1::nameTextBox1_Validated );
// Age NumericUpDown
this->ageUpDownPicker->Location = System::Drawing::Point( 112, 64 );
array<int>^temp0 = {150,0,0,0};
this->ageUpDownPicker->Maximum = System::Decimal( temp0 );
this->ageUpDownPicker->TabIndex = 4;
this->ageUpDownPicker->Validated += gcnew System::EventHandler( this, &Form1::ageUpDownPicker_Validated );
// Favorite Color ComboBox
array<Object^>^temp1 = {"None","Red","Yellow","Green","Blue","Purple"};
this->favoriteColorComboBox->Items->AddRange( temp1 );
this->favoriteColorComboBox->Location = System::Drawing::Point( 112, 96 );
this->favoriteColorComboBox->Size = System::Drawing::Size( 120, 21 );
this->favoriteColorComboBox->TabIndex = 5;
this->favoriteColorComboBox->Validated += gcnew System::EventHandler( this, &Form1::favoriteColorComboBox_Validated );
// Set up how the form should be displayed and add the controls to the form.
this->ClientSize = System::Drawing::Size( 464, 150 );
array<System::Windows::Forms::Control^>^temp2 = {this->label6,this->label5,this->label4,this->label3,this->favoriteColorComboBox,this->ageUpDownPicker,this->label2,this->label1,this->nameTextBox1};
this->Controls->AddRange( temp2 );
this->Text = "Error Provider Example";
// Create and set the ErrorProvider for each data entry control.
nameErrorProvider = gcnew System::Windows::Forms::ErrorProvider;
nameErrorProvider->SetIconAlignment( this->nameTextBox1, ErrorIconAlignment::MiddleRight );
nameErrorProvider->SetIconPadding( this->nameTextBox1, 2 );
nameErrorProvider->BlinkRate = 1000;
nameErrorProvider->BlinkStyle = System::Windows::Forms::ErrorBlinkStyle::AlwaysBlink;
ageErrorProvider = gcnew System::Windows::Forms::ErrorProvider;
ageErrorProvider->SetIconAlignment( this->ageUpDownPicker, ErrorIconAlignment::MiddleRight );
ageErrorProvider->SetIconPadding( this->ageUpDownPicker, 2 );
ageErrorProvider->BlinkStyle = System::Windows::Forms::ErrorBlinkStyle::BlinkIfDifferentError;
favoriteColorErrorProvider = gcnew System::Windows::Forms::ErrorProvider;
favoriteColorErrorProvider->SetIconAlignment( this->favoriteColorComboBox, ErrorIconAlignment::MiddleRight );
favoriteColorErrorProvider->SetIconPadding( this->favoriteColorComboBox, 2 );
favoriteColorErrorProvider->BlinkRate = 1000;
favoriteColorErrorProvider->BlinkStyle = System::Windows::Forms::ErrorBlinkStyle::NeverBlink;
}
private:
void nameTextBox1_Validated( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
if ( IsNameValid() )
{
// Clear the error, if any, in the error provider.
nameErrorProvider->SetError( this->nameTextBox1, "" );
}
else
{
// Set the error if the name is not valid.
nameErrorProvider->SetError( this->nameTextBox1, "Name is required." );
}
}
void ageUpDownPicker_Validated( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
if ( IsAgeTooYoung() )
{
// Set the error if the age is too young.
ageErrorProvider->SetError( this->ageUpDownPicker, "Age not old enough" );
}
else
if ( IsAgeTooOld() )
{
// Set the error if the age is too old.
ageErrorProvider->SetError( this->ageUpDownPicker, "Age is too old" );
}
else
{
// Clear the error, if any, in the error provider.
ageErrorProvider->SetError( this->ageUpDownPicker, "" );
}
}
void favoriteColorComboBox_Validated( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
if ( !IsColorValid() )
{
// Set the error if the favorite color is not valid.
favoriteColorErrorProvider->SetError( this->favoriteColorComboBox, "Must select a color." );
}
else
{
// Clear the error, if any, in the error provider.
favoriteColorErrorProvider->SetError( this->favoriteColorComboBox, "" );
}
}
// Functions to verify data.
bool IsNameValid()
{
// Determine whether the text box contains a zero-length String*.
return (nameTextBox1->Text->Length > 0);
}
bool IsAgeTooYoung()
{
// Determine whether the age value is less than three.
return (ageUpDownPicker->Value < 3);
}
bool IsAgeTooOld()
{
// Determine whether the age value is greater than five.
return (ageUpDownPicker->Value > 5);
}
bool IsColorValid()
{
// Determine whether the favorite color has a valid value.
return ((favoriteColorComboBox->SelectedItem != 0) && ( !favoriteColorComboBox->SelectedItem->Equals( "None" )));
}
};
[STAThread]
int main()
{
Application::Run( gcnew Form1 );
}
package ErrorProvider;
import System.*;
import System.Drawing.*;
import System.Windows.Forms.*;
public class Form1 extends System.Windows.Forms.Form
{
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Label label4;
private System.Windows.Forms.Label label5;
private System.Windows.Forms.Label label6;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.TextBox nameTextBox1;
private System.Windows.Forms.NumericUpDown ageUpDownPicker;
private System.Windows.Forms.ComboBox favoriteColorComboBox;
private System.Windows.Forms.ErrorProvider ageErrorProvider;
private System.Windows.Forms.ErrorProvider nameErrorProvider;
private System.Windows.Forms.ErrorProvider favoriteColorErrorProvider;
/** @attribute STAThread()
*/
public static void main(String[] args)
{
Application.Run(new Form1());
} //main
public Form1()
{
this.nameTextBox1 = new System.Windows.Forms.TextBox();
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.ageUpDownPicker = new System.Windows.Forms.NumericUpDown();
this.favoriteColorComboBox = new System.Windows.Forms.ComboBox();
this.label3 = new System.Windows.Forms.Label();
this.label4 = new System.Windows.Forms.Label();
this.label5 = new System.Windows.Forms.Label();
this.label6 = new System.Windows.Forms.Label();
// Name Label
this.label1.set_Location(new System.Drawing.Point(56, 32));
this.label1.set_Size(new System.Drawing.Size(40, 23));
this.label1.set_Text("Name:");
// Age Label
this.label2.set_Location(new System.Drawing.Point(40, 64));
this.label2.set_Size(new System.Drawing.Size(56, 23));
this.label2.set_Text("Age (3-5)");
// Favorite Color Label
this.label3.set_Location(new System.Drawing.Point(24, 96));
this.label3.set_Size(new System.Drawing.Size(80, 24));
this.label3.set_Text("Favorite color");
// ErrorBlinkStyle.AlwaysBlink Label
this.label4.set_Location(new System.Drawing.Point(264, 32));
this.label4.set_Size(new System.Drawing.Size(160, 23));
this.label4.set_Text("ErrorBlinkStyle.AlwaysBlink");
// ErrorBlinkStyle.BlinkIfDifferentError Label
this.label5.set_Location(new System.Drawing.Point(264, 64));
this.label5.set_Size(new System.Drawing.Size(200, 23));
this.label5.set_Text("ErrorBlinkStyle.BlinkIfDifferentError");
// ErrorBlinkStyle.NeverBlink Label
this.label6.set_Location(new System.Drawing.Point(264, 96));
this.label6.set_Size(new System.Drawing.Size(200, 23));
this.label6.set_Text("ErrorBlinkStyle.NeverBlink");
// Name TextBox
this.nameTextBox1.set_Location(new System.Drawing.Point(112, 32));
this.nameTextBox1.set_Size(new System.Drawing.Size(120, 20));
this.nameTextBox1.set_TabIndex(0);
this.nameTextBox1.add_Validated(new System.EventHandler(
this.nameTextBox1_Validated));
// Age NumericUpDown
this.ageUpDownPicker.set_Location(new System.Drawing.Point(112, 64));
this.ageUpDownPicker.set_Maximum(new System.Decimal(new int[] {
150, 0, 0, 0 }));
this.ageUpDownPicker.set_TabIndex(4);
this.ageUpDownPicker.add_Validated(new System.EventHandler(
this.ageUpDownPicker_Validated));
// Favorite Color ComboBox
this.favoriteColorComboBox.get_Items().AddRange(new Object[] {
"None", "Red", "Yellow", "Green", "Blue", "Purple" });
this.favoriteColorComboBox.set_Location(
new System.Drawing.Point(112, 96));
this.favoriteColorComboBox.set_Size(new System.Drawing.Size(120, 21));
this.favoriteColorComboBox.set_TabIndex(5);
this.favoriteColorComboBox.add_Validated(new System.EventHandler(
this.favoriteColorComboBox_Validated));
// Set up how the form should be displayed and add the controls to
// the form.
this.set_ClientSize(new System.Drawing.Size(464, 150));
this.get_Controls().AddRange(new System.Windows.Forms.Control[] {
this.label6, this.label5, this.label4, this.label3,
this.favoriteColorComboBox, this.ageUpDownPicker, this.label2,
this.label1, this.nameTextBox1 });
this.set_Text("Error Provider Example");
// Create and set the ErrorProvider for each data entry control.
nameErrorProvider = new System.Windows.Forms.ErrorProvider();
nameErrorProvider.SetIconAlignment(this.nameTextBox1,
ErrorIconAlignment.MiddleRight);
nameErrorProvider.SetIconPadding(this.nameTextBox1, 2);
nameErrorProvider.set_BlinkRate(1000);
nameErrorProvider.set_BlinkStyle(
System.Windows.Forms.ErrorBlinkStyle.AlwaysBlink);
nameErrorProvider.set_ContainerControl(this);
ageErrorProvider = new System.Windows.Forms.ErrorProvider();
ageErrorProvider.SetIconAlignment(this.ageUpDownPicker,
ErrorIconAlignment.MiddleRight);
ageErrorProvider.SetIconPadding(this.ageUpDownPicker, 2);
ageErrorProvider.set_BlinkStyle(
System.Windows.Forms.ErrorBlinkStyle.BlinkIfDifferentError);
ageErrorProvider.set_ContainerControl(this);
favoriteColorErrorProvider = new System.Windows.Forms.ErrorProvider();
favoriteColorErrorProvider.SetIconAlignment(this.favoriteColorComboBox,
ErrorIconAlignment.MiddleRight);
favoriteColorErrorProvider.SetIconPadding(this.favoriteColorComboBox, 2);
favoriteColorErrorProvider.set_BlinkRate(1000);
favoriteColorErrorProvider.set_BlinkStyle(
System.Windows.Forms.ErrorBlinkStyle.NeverBlink);
favoriteColorErrorProvider.set_ContainerControl(this);
} //Form1
private void nameTextBox1_Validated(Object sender, System.EventArgs e)
{
if (IsNameValid()) {
// Clear the error, if any, in the error provider.
nameErrorProvider.SetError(this.nameTextBox1, "");
}
else {
// Set the error if the name is not valid.
nameErrorProvider.SetError(this.nameTextBox1, "Name is required.");
}
} //nameTextBox1_Validated
private void ageUpDownPicker_Validated(Object sender, System.EventArgs e)
{
if (IsAgeTooYoung()) {
// Set the error if the age is too young.
ageErrorProvider.SetError(this.ageUpDownPicker,
"Age not old enough");
}
else {
if (IsAgeTooOld()) {
// Set the error if the age is too old.
ageErrorProvider.SetError(this.ageUpDownPicker,
"Age is too old");
}
else {
// Clear the error, if any, in the error provider.
ageErrorProvider.SetError(this.ageUpDownPicker, "");
}
}
} //ageUpDownPicker_Validated
private void favoriteColorComboBox_Validated(Object sender,
System.EventArgs e)
{
if (!(IsColorValid())) {
// Set the error if the favorite color is not valid.
favoriteColorErrorProvider.SetError(this.favoriteColorComboBox,
"Must select a color.");
}
else {
// Clear the error, if any, in the error provider.
favoriteColorErrorProvider.SetError(
this.favoriteColorComboBox, "");
}
} //favoriteColorComboBox_Validated
// Functions to verify data.
private boolean IsNameValid()
{
// Determine whether the text box contains a zero-length string.
return ((nameTextBox1.get_Text().get_Length()) > 0);
} //IsNameValid
private boolean IsAgeTooYoung()
{
// Determine whether the age value is less than three.
return (System.Convert.ToInt32(ageUpDownPicker.get_Value()) < 3);
} //IsAgeTooYoung
private boolean IsAgeTooOld()
{
// Determine whether the age value is greater than five.
return (System.Convert.ToInt32(ageUpDownPicker.get_Value()) > 5);
} //IsAgeTooOld
private boolean IsColorValid()
{
// Determine whether the favorite color has a valid value.
return (favoriteColorComboBox.get_SelectedItem() != null)
&& (!(favoriteColorComboBox.get_SelectedItem().
ToString().Equals("None")));
} //IsColorValid
} //Form1
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
请参见
参考
ErrorProvider 类
ErrorProvider 成员
System.Windows.Forms 命名空间
GetError