datagridtablestyle aa = new datagridtablestyle();
datagridboolcolumn bb = new datagridboolcolumn();
bb.allownull = false;
aa.gridcolumnstyles.add(bb);
datagrid1.tablestyles.add(aa);
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;
// 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());
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);
}
}
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";
dgtbc = new DataGridTextBoxColumn();
dgtbc.MappingName = "id";
dgtbc.HeaderText= "id";
dgt.GridColumnStyles.Add(dgtbc);
DataGridBoolColumnInherit db = new DataGridBoolColumnInherit();
db.HeaderText= "小于1000就变蓝";
db.Width= 150;
db.MappingName = "calculatedField";
db.AllowNull = false; //去掉灰色的可选状态
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();