formatting DataColumn.Expression

[J]

Is there anyway to format a calculated datacolumn? I would like the
following column to display as money (formatted as $#,##0.00). Or how about
simply displaying the column formatted as a number with only 2 decimals
(#,##0.00)?
In the sample below, amount and taxrate are existing DataColumn's.

DataColumn colTax = new DataColumn();
colTax.DataType = System.Type.GetType("System.String");
colTax.ColumnName = "tax";
myTable.Columns.Add(colTax);
colTax.Expression = "String.Format(\"{0:C}\",\"amount*taxrate\" )"; //error
: Expression does not support String.Format

[Dmitriy Lapshin [C# / .NET MVP]]

Hi,

I think the burden of formatting should be put on a presentation tier code
(e.g. the DataGrid control) and not on a DataColumn - it's just not made to
be formattable by itself.

--
Dmitriy Lapshin [C# / .NET MVP]
X-Unity Test Studio
http://x-unity.miik.com.ua/teststudio.aspx
Bring the power of unit testing to VS .NET IDE

"J" <j> wrote in message news:vn************@corp.supernews.com...

Is there anyway to format a calculated datacolumn? I would like the
following column to display as money (formatted as $#,##0.00). Or how about simply displaying the column formatted as a number with only 2 decimals
(#,##0.00)?
In the sample below, amount and taxrate are existing DataColumn's.

DataColumn colTax = new DataColumn();
colTax.DataType = System.Type.GetType("System.String");
colTax.ColumnName = "tax";
myTable.Columns.Add(colTax);
colTax.Expression = "String.Format(\"{0:C}\",\"amount*taxrate\" )"; //error : Expression does not support String.Format

[J]

The example was formatting as currency, but the principal applies to
unlimited situations.
Don't think of it as formatting for the presentation layer, think of it as
building calculated datacolumns that require use of procedures, functions,
classes, whatever. To build any kind of calculated datacolumn, except for
the most simple, requires this functionality.

"Dmitriy Lapshin [C# / .NET MVP]" <x-****@no-spam-please.hotpop.com> wrote
in message news:Ot**************@TK2MSFTNGP11.phx.gbl...

Hi,

I think the burden of formatting should be put on a presentation tier code
(e.g. the DataGrid control) and not on a DataColumn - it's just not made to be formattable by itself.

--
Dmitriy Lapshin [C# / .NET MVP]
X-Unity Test Studio
http://x-unity.miik.com.ua/teststudio.aspx
Bring the power of unit testing to VS .NET IDE

"J" <j> wrote in message news:vn************@corp.supernews.com...

Is there anyway to format a calculated datacolumn? I would like the
following column to display as money (formatted as $#,##0.00). Or how

about

simply displaying the column formatted as a number with only 2 decimals
(#,##0.00)?
In the sample below, amount and taxrate are existing DataColumn's.

DataColumn colTax = new DataColumn();
colTax.DataType = System.Type.GetType("System.String");
colTax.ColumnName = "tax";
myTable.Columns.Add(colTax);
colTax.Expression = "String.Format(\"{0:C}\",\"amount*taxrate\" )";

//error

: Expression does not support String.Format

[Dmitriy Lapshin [C# / .NET MVP]]

This seem to be limited by the allowed syntax in the Expression property
(please refer to the "DataColumn.Expression Property" topic in MSDN), which
resembles SQL and has no support for calling managed code.

--
Dmitriy Lapshin [C# / .NET MVP]
X-Unity Test Studio
http://x-unity.miik.com.ua/teststudio.aspx
Bring the power of unit testing to VS .NET IDE

"J" <j> wrote in message news:vo************@corp.supernews.com...

The example was formatting as currency, but the principal applies to
unlimited situations.
Don't think of it as formatting for the presentation layer, think of it as
building calculated datacolumns that require use of procedures, functions,
classes, whatever. To build any kind of calculated datacolumn, except for the most simple, requires this functionality.

"Dmitriy Lapshin [C# / .NET MVP]" <x-****@no-spam-please.hotpop.com> wrote
in message news:Ot**************@TK2MSFTNGP11.phx.gbl...

Hi,

I think the burden of formatting should be put on a presentation tier code (e.g. the DataGrid control) and not on a DataColumn - it's just not made

to

be formattable by itself.

--
Dmitriy Lapshin [C# / .NET MVP]
X-Unity Test Studio
http://x-unity.miik.com.ua/teststudio.aspx
Bring the power of unit testing to VS .NET IDE

"J" <j> wrote in message news:vn************@corp.supernews.com...

Is there anyway to format a calculated datacolumn? I would like the
following column to display as money (formatted as $#,##0.00). Or how

about

simply displaying the column formatted as a number with only 2 decimals (#,##0.00)?
In the sample below, amount and taxrate are existing DataColumn's.

DataColumn colTax = new DataColumn();
colTax.DataType = System.Type.GetType("System.String");
colTax.ColumnName = "tax";
myTable.Columns.Add(colTax);
colTax.Expression = "String.Format(\"{0:C}\",\"amount*taxrate\" )";

//error

: Expression does not support String.Format