CheckState Enum
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Specifies the state of a control, such as a check box, that can be checked, unchecked, or set to an indeterminate state.
public enum class CheckStatepublic enum CheckStatetype CheckState = Public Enum CheckState- Inheritance
Fields
| Name | Value | Description |
|---|---|---|
| Unchecked | 0 | The control is unchecked. |
| Checked | 1 | The control is checked. |
| Indeterminate | 2 | The control is indeterminate. An indeterminate control generally has a shaded appearance. |
Examples
The following code example demonstrates the use of the CheckState enumeration.
#using <System.Data.dll>
#using <System.Windows.Forms.dll>
#using <System.dll>
#using <System.Drawing.dll>
using namespace System;
using namespace System::Drawing;
using namespace System::Collections;
using namespace System::ComponentModel;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::IO;
public ref class Form1: public System::Windows::Forms::Form
{
private:
System::Windows::Forms::CheckedListBox^ checkedListBox1;
System::Windows::Forms::TextBox^ textBox1;
System::Windows::Forms::Button^ button1;
System::Windows::Forms::Button^ button2;
System::Windows::Forms::ListBox^ listBox1;
System::Windows::Forms::Button^ button3;
System::ComponentModel::Container^ components;
public:
Form1()
{
InitializeComponent();
// Sets up the initial objects in the CheckedListBox.
array<String^>^myFruit = {"Apples","Oranges","Tomato"};
checkedListBox1->Items->AddRange( myFruit );
// Changes the selection mode from double-click to single click.
checkedListBox1->CheckOnClick = true;
}
public:
~Form1()
{
if ( components != nullptr )
{
delete components;
}
}
private:
void InitializeComponent()
{
this->components = gcnew System::ComponentModel::Container;
this->textBox1 = gcnew System::Windows::Forms::TextBox;
this->checkedListBox1 = gcnew System::Windows::Forms::CheckedListBox;
this->listBox1 = gcnew System::Windows::Forms::ListBox;
this->button1 = gcnew System::Windows::Forms::Button;
this->button2 = gcnew System::Windows::Forms::Button;
this->button3 = gcnew System::Windows::Forms::Button;
this->textBox1->Location = System::Drawing::Point( 144, 64 );
this->textBox1->Size = System::Drawing::Size( 128, 20 );
this->textBox1->TabIndex = 1;
this->textBox1->TextChanged += gcnew System::EventHandler( this, &Form1::textBox1_TextChanged );
this->checkedListBox1->Location = System::Drawing::Point( 16, 64 );
this->checkedListBox1->Size = System::Drawing::Size( 120, 184 );
this->checkedListBox1->TabIndex = 0;
this->checkedListBox1->ItemCheck += gcnew System::Windows::Forms::ItemCheckEventHandler( this, &Form1::checkedListBox1_ItemCheck );
this->listBox1->Location = System::Drawing::Point( 408, 64 );
this->listBox1->Size = System::Drawing::Size( 128, 186 );
this->listBox1->TabIndex = 3;
this->button1->Enabled = false;
this->button1->Location = System::Drawing::Point( 144, 104 );
this->button1->Size = System::Drawing::Size( 104, 32 );
this->button1->TabIndex = 2;
this->button1->Text = "Add Fruit";
this->button1->Click += gcnew System::EventHandler( this, &Form1::button1_Click );
this->button2->Enabled = false;
this->button2->Location = System::Drawing::Point( 288, 64 );
this->button2->Size = System::Drawing::Size( 104, 32 );
this->button2->TabIndex = 2;
this->button2->Text = "Show Order";
this->button2->Click += gcnew System::EventHandler( this, &Form1::button2_Click );
this->button3->Enabled = false;
this->button3->Location = System::Drawing::Point( 288, 104 );
this->button3->Size = System::Drawing::Size( 104, 32 );
this->button3->TabIndex = 2;
this->button3->Text = "Save Order";
this->button3->Click += gcnew System::EventHandler( this, &Form1::button3_Click );
this->ClientSize = System::Drawing::Size( 563, 273 );
array<System::Windows::Forms::Control^>^temp0 = {this->listBox1,this->button3,this->button2,this->button1,this->textBox1,this->checkedListBox1};
this->Controls->AddRange( temp0 );
this->Text = "Fruit Order";
}
// Adds the string if the text box has data in it.
void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
if ( !textBox1->Text->Equals( "" ) )
{
if ( !checkedListBox1->CheckedItems->Contains( textBox1->Text ) )
checkedListBox1->Items->Add( textBox1->Text, CheckState::Checked );
textBox1->Text = "";
}
}
// Activates or deactivates the Add button.
void textBox1_TextChanged( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
if ( textBox1->Text->Equals( "" ) )
{
button1->Enabled = false;
}
else
{
button1->Enabled = true;
}
}
// Moves the checked items from the CheckedListBox to the listBox.
void button2_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
listBox1->Items->Clear();
button3->Enabled = false;
for ( int i = 0; i < checkedListBox1->CheckedItems->Count; i++ )
{
listBox1->Items->Add( checkedListBox1->CheckedItems[ i ] );
}
if ( listBox1->Items->Count > 0 )
button3->Enabled = true;
}
// Activates the move button if there are checked items.
void checkedListBox1_ItemCheck( Object^ /*sender*/, ItemCheckEventArgs^ e )
{
if ( e->NewValue == CheckState::Unchecked )
{
if ( checkedListBox1->CheckedItems->Count == 1 )
{
button2->Enabled = false;
}
}
else
{
button2->Enabled = true;
}
}
// Saves the items to a file.
void button3_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
// Insert code to save a file.
listBox1->Items->Clear();
IEnumerator^ myEnumerator;
myEnumerator = checkedListBox1->CheckedIndices->GetEnumerator();
int y;
while ( myEnumerator->MoveNext() )
{
y = safe_cast<Int32>(myEnumerator->Current);
checkedListBox1->SetItemChecked( y, false );
}
button3->Enabled = false;
}
};
[STAThread]
int main()
{
Application::Run( gcnew Form1 );
}
namespace WindowsApplication1
{
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.IO ;
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.CheckedListBox checkedListBox1;
private System.Windows.Forms.TextBox textBox1;
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.Windows.Forms.ListBox listBox1;
private System.Windows.Forms.Button button3;
private System.ComponentModel.Container components;
public Form1()
{
InitializeComponent();
// Sets up the initial objects in the CheckedListBox.
string[] myFruit = {"Apples", "Oranges","Tomato"};
checkedListBox1.Items.AddRange(myFruit);
// Changes the selection mode from double-click to single click.
checkedListBox1.CheckOnClick = true;
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.textBox1 = new System.Windows.Forms.TextBox();
this.checkedListBox1 = new System.Windows.Forms.CheckedListBox();
this.listBox1 = new System.Windows.Forms.ListBox();
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.button3 = new System.Windows.Forms.Button();
this.textBox1.Location = new System.Drawing.Point(144, 64);
this.textBox1.Size = new System.Drawing.Size(128, 20);
this.textBox1.TabIndex = 1;
this.textBox1.TextChanged += new System.EventHandler(this.textBox1_TextChanged);
this.checkedListBox1.Location = new System.Drawing.Point(16, 64);
this.checkedListBox1.Size = new System.Drawing.Size(120, 184);
this.checkedListBox1.TabIndex = 0;
this.checkedListBox1.ItemCheck += new System.Windows.Forms.ItemCheckEventHandler(this.checkedListBox1_ItemCheck);
this.listBox1.Location = new System.Drawing.Point(408, 64);
this.listBox1.Size = new System.Drawing.Size(128, 186);
this.listBox1.TabIndex = 3;
this.button1.Enabled = false;
this.button1.Location = new System.Drawing.Point(144, 104);
this.button1.Size = new System.Drawing.Size(104, 32);
this.button1.TabIndex = 2;
this.button1.Text = "Add Fruit";
this.button1.Click += new System.EventHandler(this.button1_Click);
this.button2.Enabled = false;
this.button2.Location = new System.Drawing.Point(288, 64);
this.button2.Size = new System.Drawing.Size(104, 32);
this.button2.TabIndex = 2;
this.button2.Text = "Show Order";
this.button2.Click += new System.EventHandler(this.button2_Click);
this.button3.Enabled = false;
this.button3.Location = new System.Drawing.Point(288, 104);
this.button3.Size = new System.Drawing.Size(104, 32);
this.button3.TabIndex = 2;
this.button3.Text = "Save Order";
this.button3.Click += new System.EventHandler(this.button3_Click);
this.ClientSize = new System.Drawing.Size(563, 273);
this.Controls.AddRange(new System.Windows.Forms.Control[] {this.listBox1,
this.button3,
this.button2,
this.button1,
this.textBox1,
this.checkedListBox1});
this.Text = "Fruit Order";
}
[STAThread]
public static void Main(string[] args)
{
Application.Run(new Form1());
}
// Adds the string if the text box has data in it.
private void button1_Click(object sender, System.EventArgs e)
{
if(textBox1.Text != "")
{
if(!checkedListBox1.CheckedItems.Contains(textBox1.Text))
checkedListBox1.Items.Add(textBox1.Text,CheckState.Checked);
textBox1.Text = "";
}
}
// Activates or deactivates the Add button.
private void textBox1_TextChanged(object sender, System.EventArgs e)
{
if (textBox1.Text == "")
{
button1.Enabled = false;
}
else
{
button1.Enabled = true;
}
}
// Moves the checked items from the CheckedListBox to the listBox.
private void button2_Click(object sender, System.EventArgs e)
{
listBox1.Items.Clear();
button3.Enabled=false;
for (int i=0; i< checkedListBox1.CheckedItems.Count;i++)
{
listBox1.Items.Add(checkedListBox1.CheckedItems[i]);
}
if (listBox1.Items.Count>0)
button3.Enabled=true;
}
// Activates the move button if there are checked items.
private void checkedListBox1_ItemCheck(object sender, ItemCheckEventArgs e)
{
if(e.NewValue==CheckState.Unchecked)
{
if(checkedListBox1.CheckedItems.Count==1)
{
button2.Enabled = false;
}
}
else
{
button2.Enabled = true;
}
}
// Saves the items to a file.
private void button3_Click(object sender, System.EventArgs e)
{
// Insert code to save a file.
listBox1.Items.Clear();
IEnumerator myEnumerator;
myEnumerator = checkedListBox1.CheckedIndices.GetEnumerator();
int y;
while (myEnumerator.MoveNext())
{
y =(int) myEnumerator.Current;
checkedListBox1.SetItemChecked(y, false);
}
button3.Enabled = false ;
}
}
}
Option Explicit
Option Strict
Imports System.Drawing
Imports System.Collections
Imports System.ComponentModel
Imports System.Windows.Forms
Imports System.Data
Imports System.IO
Namespace WindowsApplication1
Public Class Form1
Inherits System.Windows.Forms.Form
Private WithEvents checkedListBox1 As System.Windows.Forms.CheckedListBox
Private WithEvents textBox1 As System.Windows.Forms.TextBox
Private WithEvents button1 As System.Windows.Forms.Button
Private WithEvents button2 As System.Windows.Forms.Button
Private WithEvents listBox1 As System.Windows.Forms.ListBox
Private WithEvents button3 As System.Windows.Forms.Button
Private components As System.ComponentModel.Container
Public Sub New()
InitializeComponent()
' Sets up the initial objects in the CheckedListBox.
Dim myFruit As String() = {"Apples", "Oranges", "Tomato"}
checkedListBox1.Items.AddRange(myFruit)
' Changes the selection mode from double-click to single click.
checkedListBox1.CheckOnClick = True
End Sub
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If (components IsNot Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
Private Sub InitializeComponent()
Me.components = New System.ComponentModel.Container()
Me.textBox1 = New System.Windows.Forms.TextBox()
Me.checkedListBox1 = New System.Windows.Forms.CheckedListBox()
Me.listBox1 = New System.Windows.Forms.ListBox()
Me.button1 = New System.Windows.Forms.Button()
Me.button2 = New System.Windows.Forms.Button()
Me.button3 = New System.Windows.Forms.Button()
Me.textBox1.Location = New System.Drawing.Point(144, 64)
Me.textBox1.Size = New System.Drawing.Size(128, 20)
Me.textBox1.TabIndex = 1
Me.checkedListBox1.Location = New System.Drawing.Point(16, 64)
Me.checkedListBox1.Size = New System.Drawing.Size(120, 184)
Me.checkedListBox1.TabIndex = 0
Me.listBox1.Location = New System.Drawing.Point(408, 64)
Me.listBox1.Size = New System.Drawing.Size(128, 186)
Me.listBox1.TabIndex = 3
Me.button1.Enabled = False
Me.button1.Location = New System.Drawing.Point(144, 104)
Me.button1.Size = New System.Drawing.Size(104, 32)
Me.button1.TabIndex = 2
Me.button1.Text = "Add Fruit"
Me.button2.Enabled = False
Me.button2.Location = New System.Drawing.Point(288, 64)
Me.button2.Size = New System.Drawing.Size(104, 32)
Me.button2.TabIndex = 2
Me.button2.Text = "Show Order"
Me.button3.Enabled = False
Me.button3.Location = New System.Drawing.Point(288, 104)
Me.button3.Size = New System.Drawing.Size(104, 32)
Me.button3.TabIndex = 2
Me.button3.Text = "Save Order"
Me.ClientSize = New System.Drawing.Size(563, 273)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.listBox1, Me.button3, Me.button2, Me.button1, Me.textBox1, Me.checkedListBox1})
Me.Text = "Fruit Order"
End Sub
<STAThread()> _
Public Shared Sub Main()
Application.Run(New Form1())
End Sub
' Adds the string if the text box has data in it.
Private Sub button1_Click(sender As Object, _
e As System.EventArgs) Handles button1.Click
If textBox1.Text <> "" Then
If checkedListBox1.CheckedItems.Contains(textBox1.Text) = False Then
checkedListBox1.Items.Add(textBox1.Text, CheckState.Checked)
End If
textBox1.Text = ""
End If
End Sub
' Activates or deactivates the Add button.
Private Sub textBox1_TextChanged(sender As Object, _
e As System.EventArgs) Handles textBox1.TextChanged
If textBox1.Text = "" Then
button1.Enabled = False
Else
button1.Enabled = True
End If
End Sub
' Moves the checked items from the CheckedListBox to the listBox.
Private Sub button2_Click(sender As Object, _
e As System.EventArgs) Handles button2.Click
listBox1.Items.Clear()
button3.Enabled = False
Dim i As Integer
For i = 0 To checkedListBox1.CheckedItems.Count - 1
listBox1.Items.Add(checkedListBox1.CheckedItems(i))
Next i
If listBox1.Items.Count > 0 Then
button3.Enabled = True
End If
End Sub
' Activates the move button if there are checked items.
Private Sub checkedListBox1_ItemCheck(sender As Object, _
e As ItemCheckEventArgs) Handles checkedListBox1.ItemCheck
If e.NewValue = CheckState.Unchecked Then
If checkedListBox1.CheckedItems.Count = 1 Then
button2.Enabled = False
End If
Else
button2.Enabled = True
End If
End Sub
' Saves the items to a file.
Private Sub button3_Click(sender As Object, _
e As System.EventArgs) Handles button3.Click
' Insert code to save a file.
listBox1.Items.Clear()
For Each index in checkedListBox1.CheckedIndices.Cast(Of Integer).ToArray()
checkedListBox1.SetItemChecked(index, False)
Next
button3.Enabled = False
End Sub
End Class
End Namespace 'WindowsApplication1
Remarks
Multiple methods in CheckBox, CheckedListBox, and ItemCheckEventArgs use this enumeration.
Note
Use an indeterminately checked control when you do not want to set a default value.
Applies to
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