DataGridBoolColumn 類別
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。
指定資料行，其中每個儲存格含有用來表示布林值的核取方塊。
public ref class DataGridBoolColumn : System::Windows::Forms::DataGridColumnStylepublic class DataGridBoolColumn : System.Windows.Forms.DataGridColumnStyletype DataGridBoolColumn = class
inherit DataGridColumnStylePublic Class DataGridBoolColumn
Inherits DataGridColumnStyle- 繼承
範例
下列程式碼範例會先建立新的 DataGridBoolColumn ，並將其新增至 GridColumnStylesCollection 的 DataGridTableStyle 。
using namespace System;
using namespace System::Data;
using namespace System::Windows::Forms;
using namespace System::Drawing;
using namespace System::ComponentModel;
public ref 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 = nullptr;
count++;
}
property Color FalseColor
{
Color get()
{
return falseBrush->Color;
}
void set( Color value )
{
falseBrush = gcnew System::Drawing::SolidBrush( value );
Invalidate();
}
}
property Color TrueColor
{
Color get()
{
return trueBrush->Color;
}
void set( Color value )
{
trueBrush = gcnew System::Drawing::SolidBrush( value );
Invalidate();
}
}
property String^ Expression
{
// This will work only with a DataSet or DataTable.
// The code is not compatible with IBindingList* implementations.
String^ get()
{
return this->expressionColumn == nullptr ? String::Empty : this->expressionColumn->Expression;
}
void set( String^ value )
{
if ( expressionColumn == nullptr )
AddExpressionColumn( value );
else
expressionColumn->Expression = value;
if ( expressionColumn != nullptr && 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 == nullptr || this->DataGridTableStyle->DataGrid == nullptr )
return;
DataGrid^ myGrid = this->DataGridTableStyle->DataGrid;
DataView^ myDataView = dynamic_cast<DataView^>((dynamic_cast<CurrencyManager^>(myGrid->BindingContext[ myGrid->DataSource,myGrid->DataMember ]))->List);
// This works only with System::Data::DataTable.
if ( myDataView == nullptr )
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 != nullptr )
return;
col = gcnew DataColumn( String::Concat( "__Computed__Column__", count ) );
myDataView->Table->Columns->Add( col );
col->Expression = value;
expressionColumn = col;
}
// the OnPaint method to paint the cell based on the expression.
protected:
virtual void Paint( Graphics^ g, Rectangle bounds, CurrencyManager^ source, int rowNum, Brush^ backBrush, Brush^ foreBrush, bool alignToRight ) override
{
bool trueExpression = false;
bool hasExpression = false;
DataRowView^ drv = dynamic_cast<DataRowView^>(source->List[ rowNum ]);
hasExpression = this->expressionColumn != nullptr && this->expressionColumn->Expression != nullptr && !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 )
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 ref class MyForm: public Form
{
private:
DataTable^ myTable;
DataGrid^ myGrid;
public:
MyForm()
{
myGrid = gcnew DataGrid;
try
{
InitializeComponent();
myTable = gcnew DataTable( "NamesTable" );
myTable->Columns->Add( gcnew DataColumn( "Name" ) );
DataColumn^ column = gcnew DataColumn( "id",Int32::typeid );
myTable->Columns->Add( column );
myTable->Columns->Add( gcnew DataColumn( "calculatedField",bool::typeid ) );
DataSet^ namesDataSet = gcnew DataSet;
namesDataSet->Tables->Add( myTable );
myGrid->SetDataBinding( namesDataSet, "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 = gcnew DataGridTableStyle;
dgt->MappingName = "NamesTable";
DataGridTextBoxColumn^ dgtbc = gcnew DataGridTextBoxColumn;
dgtbc->MappingName = "Name";
dgtbc->HeaderText = "Name";
dgt->GridColumnStyles->Add( dgtbc );
dgtbc = gcnew DataGridTextBoxColumn;
dgtbc->MappingName = "id";
dgtbc->HeaderText = "id";
dgt->GridColumnStyles->Add( dgtbc );
DataGridBoolColumnInherit^ db = gcnew 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";
}
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();
}
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()
{
Application::Run( gcnew MyForm );
}
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()
{
Application.Run(new MyForm());
}
}
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);
}
}
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 (expressionColumn IsNot 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 (col IsNot 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 = (Me.expressionColumn IsNot Nothing) And (Me.expressionColumn.Expression IsNot 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
備註
DataGridBoolColumn衍生自 abstract 類別 DataGridColumnStyle 。 在執行時間， DataGridBoolColumn 每個資料格中預設都會包含三種狀態的核取方塊：已核取 () true 、未核取的 () false 和 Value 。 若要使用雙狀態核取方塊，請將 AllowNull 屬性設定為 false 。
新增至 類別的屬性包括 FalseValue 、 NullValue 和 TrueValue 。 這些屬性會指定每個資料行狀態的基礎值。
建構函式
| DataGridBoolColumn() |
初始化 DataGridBoolColumn 類別的新執行個體。 |
| DataGridBoolColumn(PropertyDescriptor) |
使用指定的 DataGridBoolColumn 初始化 PropertyDescriptor 類別的新執行個體。 |
| DataGridBoolColumn(PropertyDescriptor, Boolean) |
使用指定的 PropertyDescriptor ，初始化 類別的新實例 DataGridBoolColumn ，並指定資料行樣式是否為預設資料行。 |
屬性
方法
事件
| AlignmentChanged |
發生在 Alignment 屬性值變更時。 (繼承來源 DataGridColumnStyle) |
| AllowNullChanged |
在 AllowNull 屬性變更時發生。 |
| Disposed |
當 Dispose() 方法的呼叫處置元件時，就會發生。 (繼承來源 Component) |
| FalseValueChanged |
在 FalseValue 屬性變更時發生。 |
| FontChanged |
發生於資料行的字型變更時。 (繼承來源 DataGridColumnStyle) |
| HeaderTextChanged |
發生在 HeaderText 屬性值變更時。 (繼承來源 DataGridColumnStyle) |
| MappingNameChanged |
發生於 MappingName 值變更時。 (繼承來源 DataGridColumnStyle) |
| NullTextChanged |
發生於 NullText 值變更時。 (繼承來源 DataGridColumnStyle) |
| PropertyDescriptorChanged |
發生在 PropertyDescriptor 屬性值變更時。 (繼承來源 DataGridColumnStyle) |
| ReadOnlyChanged |
發生在 ReadOnly 屬性值變更時。 (繼承來源 DataGridColumnStyle) |
| TrueValueChanged |
發生於 TrueValue 屬性值變更時。 |
| WidthChanged |
發生在 Width 屬性值變更時。 (繼承來源 DataGridColumnStyle) |
明確介面實作
| IDataGridColumnStyleEditingNotificationService.ColumnStartedEditing(Control) |
通知 DataGrid 控制項，使用者已開始編輯資料行。 (繼承來源 DataGridColumnStyle) |
