ErrorIconAlignment Enumeration
Specifies constants indicating the locations that an error icon can appear in relation to the control with an error.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
| Member name | Description | |
|---|---|---|
| BottomLeft | The icon appears aligned with the bottom of the control and the left of the control. | |
| BottomRight | The icon appears aligned with the bottom of the control and the right of the control. | |
| MiddleLeft | The icon appears aligned with the middle of the control and the left of the control. | |
| MiddleRight | The icon appears aligned with the middle of the control and the right of the control. | |
| TopLeft | The icon appears aligned with the top of the control and to the left of the control. | |
| TopRight | The icon appears aligned with the top of the control and to the right of the control. |
This enumeration is used by ErrorProvider.
The following example demonstrates using the ErrorProvider class to notify the user of a data entry error. The example creates a Form that contains a TextBox control, a NumericUpDown control, and a ComboBox control, each validating its content, and an ErrorProvider for each control. The example sets error icon options using the BlinkRate and BlinkStyle properties and the SetIconAlignment and SetIconPadding methods. The SetError method is called with or without appropriate error text during a control's Validated event, depending upon the content in the control.
#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, String.Empty ); } 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, String.Empty ); } } 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, String.Empty ); } } // 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 ); }
Available since 1.1