Specifies a column in which each cell contains a check box for representing a Boolean value.
For a list of all members of this type, see DataGridBoolColumn Members.
System.Object
System.MarshalByRefObject
System.ComponentModel.Component
System.Windows.Forms.DataGridColumnStyle
System.Windows.Forms.DataGridBoolColumn
[Visual Basic]
Public Class DataGridBoolColumn
Inherits DataGridColumnStyle
[C#]
public class DataGridBoolColumn : DataGridColumnStyle
[C++]
public __gc class DataGridBoolColumn : public DataGridColumnStyle
[JScript]
public class DataGridBoolColumn extends DataGridColumnStyle
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Remarks
The DataGridBoolColumn derives from the abstract (MustInherit in Visual Basic) class DataGridColumnStyle. At run time, the DataGridBoolColumn contains check boxes in each cell that have three states: checked (true), unchecked (false), and DBNull.Value.
Properties added to the class include FalseValue, NullValue, and TrueValue. These properties specify the value underlying each of the column's states.
Example
[Visual Basic, C#, C++] The following example first creates a new DataGridBoolColumn object and adds it to the GridColumnStylesCollection of a DataGridTableStyle object.
[Visual Basic]
Imports System
Imports System.Data
Imports System.Windows.Forms
Imports System.Drawing
Imports System.ComponentModel
Public Class MyForm
Inherits System.Windows.Forms.Form
Private components As System.ComponentModel.Container
Private myTable As DataTable
Private myGrid As DataGrid = New DataGrid()
Public Shared Sub Main()
Application.Run(New MyForm())
End Sub
Public Sub New()
Try
InitializeComponent()
myTable = New DataTable("NamesTable")
myTable.Columns.Add(New DataColumn("Name"))
Dim column As DataColumn = New DataColumn _
("id", GetType(System.Int32))
myTable.Columns.Add(column)
myTable.Columns.Add(New DataColumn _
("calculatedField", GetType(Boolean)))
Dim namesDataSet As DataSet = New DataSet("myDataSet")
namesDataSet.Tables.Add(myTable)
myGrid.SetDataBinding(namesDataSet, "NamesTable")
AddData()
AddTableStyle()
Catch exc As System.Exception
Console.WriteLine(exc.ToString)
End Try
End Sub
Private Sub AddTableStyle()
' Map a new TableStyle to the DataTable. Then
' add DataGridColumnStyle objects to the collection
' of column styles with appropriate mappings.
Dim dgt As DataGridTableStyle = New DataGridTableStyle()
dgt.MappingName = "NamesTable"
Dim dgtbc As DataGridTextBoxColumn = _
New DataGridTextBoxColumn()
dgtbc.MappingName = "Name"
dgtbc.HeaderText = "Name"
dgt.GridColumnStyles.Add(dgtbc)
dgtbc = New DataGridTextBoxColumn()
dgtbc.MappingName = "id"
dgtbc.HeaderText = "id"
dgt.GridColumnStyles.Add(dgtbc)
Dim db As DataGridBoolColumnInherit = _
New DataGridBoolColumnInherit()
db.HeaderText = "less than 1000 = blue"
db.Width = 150
db.MappingName = "calculatedField"
dgt.GridColumnStyles.Add(db)
myGrid.TableStyles.Add(dgt)
' This expression instructs the grid to change
' the color of the inherited DataGridBoolColumn
' according to the value of the id field. If it's
' less than 1000, the row is blue. Otherwise,
' the color is yellow.
db.Expression = "id < 1000"
End Sub
Private Sub AddData()
' Add data with varying numbers for the id field.
' If the number is over 1000, the cell will paint
' yellow. Otherwise, it will be blue.
Dim dRow As DataRow
dRow = myTable.NewRow()
dRow("Name") = "name 1"
dRow("id") = 999
myTable.Rows.Add(dRow)
dRow = myTable.NewRow()
dRow("Name") = "name 2"
dRow("id") = 2300
myTable.Rows.Add(dRow)
dRow = myTable.NewRow()
dRow("Name") = "name 3"
dRow("id") = 120
myTable.Rows.Add(dRow)
dRow = myTable.NewRow()
dRow("Name") = "name 4"
dRow("id") = 4023
myTable.Rows.Add(dRow)
dRow = myTable.NewRow()
dRow("Name") = "name 5"
dRow("id") = 2345
myTable.Rows.Add(dRow)
myTable.AcceptChanges()
End Sub
Private Sub InitializeComponent()
Me.Size = New Size(500, 500)
myGrid.Size = New Size(350, 250)
myGrid.TabStop = True
myGrid.TabIndex = 1
Me.StartPosition = FormStartPosition.CenterScreen
Me.Controls.Add(myGrid)
End Sub
End Class
Public Class DataGridBoolColumnInherit
Inherits DataGridBoolColumn
Private trueBrush As SolidBrush = Brushes.Blue
Private falseBrush As SolidBrush = Brushes.Yellow
Private expressionColumn As DataColumn = Nothing
Shared count As Int32 = 0
Public Property FalseColor() As Color
Get
Return falseBrush.Color
End Get
Set(ByVal Value As Color)
falseBrush = New SolidBrush(Value)
Invalidate()
End Set
End Property
Public Property TrueColor() As Color
Get
Return trueBrush.Color
End Get
Set(ByVal Value As Color)
trueBrush = New SolidBrush(Value)
Invalidate()
End Set
End Property
Public Sub New()
count += 1
End Sub
' This will work only with a DataSet or DataTable.
' The code is not compatible with IBindingList implementations.
Public Property Expression() As String
Get
If Me.expressionColumn Is Nothing Then
Return String.Empty
Else
Return Me.expressionColumn.Expression
End If
End Get
Set(ByVal Value As String)
If expressionColumn Is Nothing Then
AddExpressionColumn(Value)
Else
expressionColumn.Expression = Value
End If
If Not (expressionColumn Is Nothing) And expressionColumn.Expression.Equals(Value) Then
Return
End If
Invalidate()
End Set
End Property
Private Sub AddExpressionColumn(ByVal value As String)
' Get the grid's data source. First check for a null
' table or data grid.
If Me.DataGridTableStyle Is Nothing Or _
Me.DataGridTableStyle.DataGrid Is Nothing Then
Return
End If
Dim dg As DataGrid = Me.DataGridTableStyle.DataGrid
Dim dv As DataView = CType(dg.BindingContext(dg.DataSource, dg.DataMember), CurrencyManager).List
' This works only with System.Data.DataTable.
If dv Is Nothing Then
Return
End If
' If the user already added a column with the name
' then exit. Otherwise, add the column and set the
' expression to the value passed to this function.
Dim col As DataColumn = dv.Table.Columns("__Computed__Column__")
If Not (col Is Nothing) Then
Return
End If
col = New DataColumn("__Computed__Column__" + count.ToString())
dv.Table.Columns.Add(col)
col.Expression = value
expressionColumn = col
End Sub
' Override the OnPaint method to paint the cell based on the expression.
Protected Overloads Overrides Sub Paint _
(ByVal g As Graphics, _
ByVal bounds As Rectangle, _
ByVal [source] As CurrencyManager, _
ByVal rowNum As Integer, _
ByVal backBrush As Brush, _
ByVal foreBrush As Brush, _
ByVal alignToRight As Boolean)
Dim trueExpression As Boolean = False
Dim hasExpression As Boolean = False
Dim drv As DataRowView = [source].List(rowNum)
hasExpression = Not (Me.expressionColumn Is Nothing) And Not (Me.expressionColumn.Expression Is Nothing) And Not Me.expressionColumn.Expression.Equals([String].Empty)
' Get the value from the expression column.
' For simplicity, we assume a True/False value for the
' expression column.
If hasExpression Then
Dim expr As Object = drv.Row(expressionColumn.ColumnName)
trueExpression = expr.Equals("True")
End If
' Let the DataGridBoolColumn do the painting.
If Not hasExpression Then
MyBase.Paint(g, bounds, [source], rowNum, backBrush, foreBrush, alignToRight)
End If
' Paint using the expression color for true or false, as calculated.
If trueExpression Then
MyBase.Paint(g, bounds, [source], rowNum, trueBrush, foreBrush, alignToRight)
Else
MyBase.Paint(g, bounds, [source], rowNum, falseBrush, foreBrush, alignToRight)
End If
End Sub
End Class
[C#]
using System;
using System.Data;
using System.Windows.Forms;
using System.Drawing;
using System.ComponentModel;
public class MyForm : Form
{
private DataTable myTable;
private DataGrid myGrid = new DataGrid();
public MyForm() : base()
{
try
{
InitializeComponent();
myTable = new DataTable("NamesTable");
myTable.Columns.Add(new DataColumn("Name"));
DataColumn column = new DataColumn
("id", typeof(System.Int32));
myTable.Columns.Add(column);
myTable.Columns.Add(new
DataColumn("calculatedField", typeof(bool)));
DataSet namesDataSet = new DataSet();
namesDataSet.Tables.Add(myTable);
myGrid.SetDataBinding(namesDataSet, "NamesTable");
AddTableStyle();
AddData();
}
catch (System.Exception exc)
{
Console.WriteLine(exc.ToString());
}
}
private void grid_Enter(object sender, EventArgs e)
{
myGrid.CurrentCell = new DataGridCell(2,2);
}
private void AddTableStyle()
{
// Map a new TableStyle to the DataTable. Then
// add DataGridColumnStyle objects to the collection
// of column styles with appropriate mappings.
DataGridTableStyle dgt = new DataGridTableStyle();
dgt.MappingName = "NamesTable";
DataGridTextBoxColumn dgtbc = new DataGridTextBoxColumn();
dgtbc.MappingName = "Name";
dgtbc.HeaderText= "Name";
dgt.GridColumnStyles.Add(dgtbc);
dgtbc = new DataGridTextBoxColumn();
dgtbc.MappingName = "id";
dgtbc.HeaderText= "id";
dgt.GridColumnStyles.Add(dgtbc);
DataGridBoolColumnInherit db =
new DataGridBoolColumnInherit();
db.HeaderText= "less than 1000 = blue";
db.Width= 150;
db.MappingName = "calculatedField";
dgt.GridColumnStyles.Add(db);
myGrid.TableStyles.Add(dgt);
// This expression instructs the grid to change
// the color of the inherited DataGridBoolColumn
// according to the value of the id field. If it's
// less than 1000, the row is blue. Otherwise,
// the color is yellow.
db.Expression = "id < 1000";
}
private void AddData()
{
// Add data with varying numbers for the id field.
// If the number is over 1000, the cell will paint
// yellow. Otherwise, it will be blue.
DataRow dRow = myTable.NewRow();
dRow["Name"] = "name 1 ";
dRow["id"] = 999;
myTable.Rows.Add(dRow);
dRow = myTable.NewRow();
dRow["Name"] = "name 2";
dRow["id"] = 2300;
myTable.Rows.Add(dRow);
dRow = myTable.NewRow();
dRow["Name"] = "name 3";
dRow["id"] = 120;
myTable.Rows.Add(dRow);
dRow = myTable.NewRow();
dRow["Name"] = "name 4";
dRow["id"] = 4023;
myTable.Rows.Add(dRow);
dRow = myTable.NewRow();
dRow["Name"] = "name 5";
dRow["id"] = 2345;
myTable.Rows.Add(dRow);
myTable.AcceptChanges();
}
private void InitializeComponent()
{
this.Size = new Size(500, 500);
myGrid.Size = new Size(350, 250);
myGrid.TabStop = true;
myGrid.TabIndex = 1;
this.StartPosition = FormStartPosition.CenterScreen;
this.Controls.Add(myGrid);
}
[STAThread]
public static void Main()
{
MyForm myGridForm = new MyForm();
myGridForm.ShowDialog();
}
}
public class DataGridBoolColumnInherit : DataGridBoolColumn
{
private SolidBrush trueBrush = Brushes.Blue as SolidBrush;
private SolidBrush falseBrush = Brushes.Yellow as SolidBrush;
private DataColumn expressionColumn = null;
private static int count = 0;
public Color FalseColor
{
get
{
return falseBrush.Color;
}
set
{
falseBrush = new SolidBrush(value);
Invalidate();
}
}
public Color TrueColor
{
get
{
return trueBrush.Color;
}
set
{
trueBrush = new SolidBrush(value);
Invalidate();
}
}
public DataGridBoolColumnInherit() : base ()
{
count ++;
}
// This will work only with a DataSet or DataTable.
// The code is not compatible with IBindingList implementations.
public string Expression
{
get
{
return this.expressionColumn == null ? String.Empty :
this.expressionColumn.Expression;
}
set
{
if (expressionColumn == null)
AddExpressionColumn(value);
else
expressionColumn.Expression = value;
if (expressionColumn != null &&
expressionColumn.Expression.Equals(value))
return;
Invalidate();
}
}
private void AddExpressionColumn(string value)
{
// Get the grid's data source. First check for a null
// table or data grid.
if (this.DataGridTableStyle == null ||
this.DataGridTableStyle.DataGrid == null)
return;
DataGrid myGrid = this.DataGridTableStyle.DataGrid;
DataView myDataView = ((CurrencyManager)
myGrid.BindingContext[myGrid.DataSource,
myGrid.DataMember]).List
as DataView;
// This works only with System.Data.DataTable.
if (myDataView == null)
return;
// If the user already added a column with the name
// then exit. Otherwise, add the column and set the
// expression to the value passed to this function.
DataColumn col = myDataView.Table.Columns["__Computed__Column__"];
if (col != null)
return;
col = new DataColumn("__Computed__Column__" + count.ToString());
myDataView.Table.Columns.Add(col);
col.Expression = value;
expressionColumn = col;
}
// override the OnPaint method to paint the cell based on the expression.
protected override void Paint(Graphics g, Rectangle bounds,
CurrencyManager source, int rowNum,
Brush backBrush, Brush foreBrush,
bool alignToRight)
{
bool trueExpression = false;
bool hasExpression = false;
DataRowView drv = source.List[rowNum] as DataRowView;
hasExpression = this.expressionColumn != null &&
this.expressionColumn.Expression != null &&
!this.expressionColumn.Expression.Equals(String.Empty);
Console.WriteLine(string.Format("hasExpressionValue {0}",hasExpression));
// Get the value from the expression column.
// For simplicity, we assume a True/False value for the
// expression column.
if (hasExpression)
{
object expr = drv.Row[expressionColumn.ColumnName];
trueExpression = expr.Equals("True");
}
// Let the DataGridBoolColumn do the painting.
if (!hasExpression)
base.Paint(g, bounds, source, rowNum,
backBrush, foreBrush, alignToRight);
// Paint using the expression color for true or false, as calculated.
if (trueExpression)
base.Paint(g, bounds, source, rowNum,
trueBrush, foreBrush, alignToRight);
else
base.Paint(g, bounds, source, rowNum,
falseBrush, foreBrush, alignToRight);
}
}
[C++]
using namespace System;
using namespace System::Data;
using namespace System::Windows::Forms;
using namespace System::Drawing;
using namespace System::ComponentModel;
public __gc class DataGridBoolColumnInherit : public DataGridBoolColumn {
private:
SolidBrush* trueBrush;
SolidBrush* falseBrush;
DataColumn* expressionColumn;
static int count = 0;
public:
DataGridBoolColumnInherit() : DataGridBoolColumn() {
trueBrush = dynamic_cast<SolidBrush*>(Brushes::Blue);
falseBrush = dynamic_cast<SolidBrush*>(Brushes::Yellow);
expressionColumn = 0;
count ++;
}
__property Color get_FalseColor() {
return falseBrush->Color;
}
__property void set_FalseColor(Color value) {
falseBrush = new System::Drawing::SolidBrush(value);
Invalidate();
}
__property Color get_TrueColor() {
return trueBrush->Color;
}
__property void set_TrueColor(Color value) {
trueBrush = new System::Drawing::SolidBrush(value);
Invalidate();
}
// This will work only with a DataSet or DataTable.
// The code is not compatible with IBindingList* implementations.
__property String* get_Expression() {
return this->expressionColumn == 0 ? String::Empty :
this->expressionColumn->Expression;
}
__property void set_Expression(String* value) {
if (expressionColumn == 0)
AddExpressionColumn(value);
else
expressionColumn->Expression = value;
if (expressionColumn != 0 &&
expressionColumn->Expression->Equals(value))
return;
Invalidate();
}
private:
void AddExpressionColumn(String* value) {
// Get the grid's data source. First check for a 0
// table or data grid.
if (this->DataGridTableStyle == 0 ||
this->DataGridTableStyle->DataGrid == 0)
return;
DataGrid* myGrid = this->DataGridTableStyle->DataGrid;
DataView* myDataView = dynamic_cast<DataView*>(
(dynamic_cast<CurrencyManager*>(
myGrid->BindingContext->Item[myGrid->DataSource,
myGrid->DataMember]))->List);
// This works only with System::Data::DataTable.
if (myDataView == 0)
return;
// If the user already added a column with the name
// then exit. Otherwise, add the column and set the
// expression to the value passed to this function.
DataColumn* col =
myDataView->Table->Columns->Item[S"__Computed__Column__"];
if (col != 0)
return;
col = new DataColumn(String::Concat(
S"__Computed__Column__", __box(count)));
myDataView->Table->Columns->Add(col);
col->Expression = value;
expressionColumn = col;
}
// the OnPaint method to paint the cell based on the expression.
protected:
void Paint(Graphics* g, Rectangle bounds,
CurrencyManager* source, int rowNum,
Brush* backBrush, Brush* foreBrush,
bool alignToRight) {
bool trueExpression = false;
bool hasExpression = false;
DataRowView* drv = dynamic_cast<DataRowView*>(source->List->Item[rowNum]);
hasExpression = this->expressionColumn != 0 &&
this->expressionColumn->Expression != 0 &&
!this->expressionColumn->Expression->Equals(String::Empty);
Console::WriteLine(String::Format(S"hasExpressionValue {0}", __box(hasExpression)));
// Get the value from the expression column.
// For simplicity, we assume a True/False value for the
// expression column.
if (hasExpression) {
Object* expr = drv->Row->Item[expressionColumn->ColumnName];
trueExpression = expr->Equals(S"True");
}
// Let the DataGridBoolColumn do the painting.
if (!hasExpression)
DataGridBoolColumn::Paint(g, bounds, source, rowNum,
backBrush, foreBrush, alignToRight);
// Paint using the expression color for true or false, as calculated.
if (trueExpression)
DataGridBoolColumn::Paint(g, bounds, source, rowNum,
trueBrush, foreBrush, alignToRight);
else
DataGridBoolColumn::Paint(g, bounds, source, rowNum,
falseBrush, foreBrush, alignToRight);
}
};
public __gc class MyForm : public Form {
private:
DataTable* myTable;
DataGrid* myGrid;
public:
MyForm() {
myGrid = new DataGrid();
try {
InitializeComponent();
myTable = new DataTable(S"NamesTable");
myTable->Columns->Add(new DataColumn(S"Name"));
DataColumn* column = new DataColumn
(S"id", __typeof(System::Int32));
myTable->Columns->Add(column);
myTable->Columns->Add(new
DataColumn(S"calculatedField", __typeof(bool)));
DataSet* namesDataSet = new DataSet();
namesDataSet->Tables->Add(myTable);
myGrid->SetDataBinding(namesDataSet, S"NamesTable");
AddTableStyle();
AddData();
} catch (System::Exception* exc) {
Console::WriteLine(exc);
}
}
private:
void grid_Enter(Object* sender, EventArgs* e) {
myGrid->CurrentCell = DataGridCell(2, 2);
}
void AddTableStyle() {
// Map a new TableStyle to the DataTable. Then
// add DataGridColumnStyle objects to the collection
// of column styles with appropriate mappings.
DataGridTableStyle* dgt = new DataGridTableStyle();
dgt->MappingName = S"NamesTable";
DataGridTextBoxColumn* dgtbc = new DataGridTextBoxColumn();
dgtbc->MappingName = S"Name";
dgtbc->HeaderText= S"Name";
dgt->GridColumnStyles->Add(dgtbc);
dgtbc = new DataGridTextBoxColumn();
dgtbc->MappingName = S"id";
dgtbc->HeaderText= S"id";
dgt->GridColumnStyles->Add(dgtbc);
DataGridBoolColumnInherit* db = new DataGridBoolColumnInherit();
db->HeaderText= S"less than 1000 = blue";
db->Width= 150;
db->MappingName = S"calculatedField";
dgt->GridColumnStyles->Add(db);
myGrid->TableStyles->Add(dgt);
// This expression instructs the grid to change
// the color of the inherited DataGridBoolColumn
// according to the value of the id field. If it's
// less than 1000, the row is blue. Otherwise,
// the color is yellow.
db->Expression = S"id < 1000";
}
void AddData() {
// Add data with varying numbers for the id field.
// If the number is over 1000, the cell will paint
// yellow. Otherwise, it will be blue.
DataRow* dRow = myTable->NewRow();
dRow->Item[S"Name"] = S"name 1 ";
dRow->Item[S"id"] = __box(999);
myTable->Rows->Add(dRow);
dRow = myTable->NewRow();
dRow->Item[S"Name"] = S"name 2";
dRow->Item[S"id"] = __box(2300);
myTable->Rows->Add(dRow);
dRow = myTable->NewRow();
dRow->Item[S"Name"] = S"name 3";
dRow->Item[S"id"] = __box(120);
myTable->Rows->Add(dRow);
dRow = myTable->NewRow();
dRow->Item[S"Name"] = S"name 4";
dRow->Item[S"id"] = __box(4023);
myTable->Rows->Add(dRow);
dRow = myTable->NewRow();
dRow->Item[S"Name"] = S"name 5";
dRow->Item[S"id"] = __box(2345);
myTable->Rows->Add(dRow);
myTable->AcceptChanges();
}
void InitializeComponent() {
this->Size = System::Drawing::Size(500, 500);
myGrid->Size = System::Drawing::Size(350, 250);
myGrid->TabStop = true;
myGrid->TabIndex = 1;
this->StartPosition = FormStartPosition::CenterScreen;
this->Controls->Add(myGrid);
}
};
[STAThread]
int main() {
MyForm* myGridForm = new MyForm();
myGridForm->ShowDialog();
}
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button .gif)
in the upper-left corner of the page.
Requirements
Namespace: System.Windows.Forms
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
See Also
DataGridBoolColumn Members | System.Windows.Forms Namespace | DataColumn | DataGrid | DataGridColumnStyle | GridColumnStylesCollection | GetType | Type