The DataGrid Web control was designed to render data into an HTML table tag, as was shown in figure That is, for each row in the DataGrid's DataSource, an HTML table row (tr) is added, and for each column in each row a table column cell is added (td).

The DataGrid declaration shown in line 29 of code image was the DataGrid in its simplest form: simply displaying all the rows and columns in the DataSource using the default formatting options. code does not show is the DataGrid's rich set of capabilities, which include the following:

Many of the features listed here and more will be covered later in the book. In this section, the only feature we'll examine in any detail is the first one. We will also discuss some of the features of the DataGrid that are not present in the DataList or Repeater.

the DataGrid will display all fields in the DataSource in the order they appear by default. However, there might be times when you only want to display a subset of the fields in the DataSource, or you want them to appear in a different left-to-right ordering. The AutoGenerateColumns property of the DataGrid class indicates whether all the DataSource's fields will be automatically added to the DataGrid; by default this property is set to True.

If you want to specify what fields should appear in the DataGrid Web control, you should first make sure that the AutoGenerateColumns property is set to False and then add a Columns tag that explicitly lists the fields that you want to appear.

You can use the BoundColumn control to explicitly add a column to the Columns tag. The vital property of the BoundColumn control is the DataField property, which specifies the column name in the DataSource that you want to display. If this is not quite clear, hopefully an example will help!

code contains the same source code from codeDataSource, we set the AutoGenerateColumns property to False, and then explicitly list the fields we'd like to have present in our DataGrid in the Columns section using BoundColumn controls.