| title | description | ms.date | helpviewer_keywords | ms.assetid | |||
|---|---|---|---|---|---|---|---|
Sizing Options in the DataGrid Control |
Learn how to set individual rows and columns in the Windows Presentation Foundation DataGrid control to size to their contents or to specific values. |
03/30/2017 |
|
96a0e47e-b010-4302-98ef-2daac446d8db |
Various options are available to control how the xref:System.Windows.Controls.DataGrid sizes itself. The xref:System.Windows.Controls.DataGrid, and individual rows and columns in the xref:System.Windows.Controls.DataGrid, can be set to size automatically to their contents or can be set to specific values. By default, the xref:System.Windows.Controls.DataGrid will grow and shrink to fit the size of its contents.
By default, the xref:System.Windows.FrameworkElement.Height%2A and xref:System.Windows.FrameworkElement.Width%2A properties of the xref:System.Windows.Controls.DataGrid are set to xref:System.Double.NaN?displayProperty=nameWithType ("Auto" in XAML), and the xref:System.Windows.Controls.DataGrid will adjust to the size of its contents.
When placed inside a container that does not restrict the size of its children, such as a xref:System.Windows.Controls.Canvas or xref:System.Windows.Controls.StackPanel, the xref:System.Windows.Controls.DataGrid will stretch beyond the visible bounds of the container and scrollbars will not be shown. This condition has both usability and performance implications.
When bound to a data set, if the xref:System.Windows.FrameworkElement.Height%2A of the xref:System.Windows.Controls.DataGrid is not restricted, it will continue to add a row for each data item in the bound data set. This can cause the xref:System.Windows.Controls.DataGrid to grow outside the visible bounds of your application as rows are added. The xref:System.Windows.Controls.DataGrid will not show scrollbars in this case because its xref:System.Windows.FrameworkElement.Height%2A will continue to grow to accommodate the new rows.
An object is created for each row in the xref:System.Windows.Controls.DataGrid. If you are working with a large data set and you allow the xref:System.Windows.Controls.DataGrid to automatically size itself, the creation of a large number of objects may affect the performance of your application.
To avoid these issues when you work with large data sets, it is recommended that you specifically set the xref:System.Windows.FrameworkElement.Height%2A of the xref:System.Windows.Controls.DataGrid or place it in a container that will restrict its xref:System.Windows.FrameworkElement.Height%2A, such as a xref:System.Windows.Controls.Grid. When the xref:System.Windows.FrameworkElement.Height%2A is restricted, the xref:System.Windows.Controls.DataGrid will only create the rows that will fit within its specified xref:System.Windows.FrameworkElement.Height%2A, and will recycle those rows as needed to display new data.
The xref:System.Windows.Controls.DataGrid can be set to automatically size within specified boundaries, or the xref:System.Windows.Controls.DataGrid can be set to a specific size. The following table shows the properties that can be set to control the xref:System.Windows.Controls.DataGrid size.
| Property | Description |
|---|---|
| xref:System.Windows.FrameworkElement.Height%2A | Sets a specific height for the xref:System.Windows.Controls.DataGrid. |
| xref:System.Windows.FrameworkElement.MaxHeight%2A | Sets the upper bound for the height of the xref:System.Windows.Controls.DataGrid. The xref:System.Windows.Controls.DataGrid will grow vertically until it reaches this height. |
| xref:System.Windows.FrameworkElement.MinHeight%2A | Sets the lower bound for the height of the xref:System.Windows.Controls.DataGrid. The xref:System.Windows.Controls.DataGrid will shrink vertically until it reaches this height. |
| xref:System.Windows.FrameworkElement.Width%2A | Sets a specific width for the xref:System.Windows.Controls.DataGrid. |
| xref:System.Windows.FrameworkElement.MaxWidth%2A | Sets the upper bound for the width of the xref:System.Windows.Controls.DataGrid. The xref:System.Windows.Controls.DataGrid will grow horizontally until it reaches this width. |
| xref:System.Windows.FrameworkElement.MinWidth%2A | Sets the lower bound for the width of the xref:System.Windows.Controls.DataGrid. The xref:System.Windows.Controls.DataGrid will shrink horizontally until it reaches this width. |
By default, a xref:System.Windows.Controls.DataGrid row's xref:System.Windows.FrameworkElement.Height%2A property is set to xref:System.Double.NaN?displayProperty=nameWithType ("Auto" in XAML), and the row height will expand to the size of its contents. The height of all rows in the xref:System.Windows.Controls.DataGrid can be specified by setting the xref:System.Windows.Controls.DataGrid.RowHeight%2A?displayProperty=nameWithType property. Users can change the row height by dragging the row header dividers.
To display row headers, the xref:System.Windows.Controls.DataGrid.HeadersVisibility%2A property must be set to xref:System.Windows.Controls.DataGridHeadersVisibility.Row?displayProperty=nameWithType or xref:System.Windows.Controls.DataGridHeadersVisibility.All?displayProperty=nameWithType. By default, row headers are displayed and they automatically size to fit their content. The row headers can be given a specific width by setting the xref:System.Windows.Controls.DataGrid.RowHeaderWidth%2A?displayProperty=nameWithType property.
The xref:System.Windows.Controls.DataGrid uses values of the xref:System.Windows.Controls.DataGridLength and the xref:System.Windows.Controls.DataGridLengthUnitType structure to specify absolute or automatic sizing modes.
The following table shows the values provided by the xref:System.Windows.Controls.DataGridLengthUnitType structure.
| Name | Description |
|---|---|
| xref:System.Windows.Controls.DataGridLengthUnitType.Auto | The default automatic sizing mode sizes xref:System.Windows.Controls.DataGrid columns based on the contents of both cells and column headers. |
| xref:System.Windows.Controls.DataGridLengthUnitType.SizeToCells | The cell-based automatic sizing mode sizes xref:System.Windows.Controls.DataGrid columns based on the contents of cells in the column, not including column headers. |
| xref:System.Windows.Controls.DataGridLengthUnitType.SizeToHeader | The header-based automatic sizing mode sizes xref:System.Windows.Controls.DataGrid columns based on the contents of column headers only. |
| xref:System.Windows.Controls.DataGridLengthUnitType.Pixel | The pixel-based sizing mode sizes xref:System.Windows.Controls.DataGrid columns based on the numeric value provided. |
| xref:System.Windows.Controls.DataGridLengthUnitType.Star | The star sizing mode is used to distribute available space by weighted proportions. In XAML, star values are expressed as n* where n represents a numeric value. 1* is equivalent to *. For example, if two columns in a xref:System.Windows.Controls.DataGrid had widths of * and 2*, the first column would receive one portion of the available space and the second column would receive two portions of the available space. |
The xref:System.Windows.Controls.DataGridLengthConverter class can be used to convert data between numeric or string values and xref:System.Windows.Controls.DataGridLength values.
By default, the xref:System.Windows.Controls.DataGrid.ColumnWidth%2A?displayProperty=nameWithType property is set to xref:System.Windows.Controls.DataGridLength.SizeToHeader%2A, and the xref:System.Windows.Controls.DataGridColumn.Width%2A?displayProperty=nameWithType property is set to xref:System.Windows.Controls.DataGridLength.Auto%2A. When the sizing mode is set to xref:System.Windows.Controls.DataGridLength.Auto%2A or xref:System.Windows.Controls.DataGridLength.SizeToCells%2A, columns will grow to the width of their widest visible content. When scrolling, these sizing modes will cause columns to expand if content that is larger than the current column size is scrolled into view. The column will not shrink after the content is scrolled out of view.
Columns in the xref:System.Windows.Controls.DataGrid can also be set to automatically size only within specified boundaries, or columns can be set to a specific size. The following table shows the properties that can be set to control column sizes.
| Property | Description |
|---|---|
| xref:System.Windows.Controls.DataGrid.MaxColumnWidth%2A?displayProperty=nameWithType | Sets the upper bound for all columns in the xref:System.Windows.Controls.DataGrid. |
| xref:System.Windows.Controls.DataGridColumn.MaxWidth%2A?displayProperty=nameWithType | Sets the upper bound for an individual column. Overrides xref:System.Windows.Controls.DataGrid.MaxColumnWidth%2A?displayProperty=nameWithType. |
| xref:System.Windows.Controls.DataGrid.MinColumnWidth%2A?displayProperty=nameWithType | Sets the lower bound for all columns in the xref:System.Windows.Controls.DataGrid. |
| xref:System.Windows.Controls.DataGridColumn.MinWidth%2A?displayProperty=nameWithType | Sets the lower bound for an individual column. Overrides xref:System.Windows.Controls.DataGrid.MinColumnWidth%2A?displayProperty=nameWithType. |
| xref:System.Windows.Controls.DataGrid.ColumnWidth%2A?displayProperty=nameWithType | Sets a specific width for all columns in the xref:System.Windows.Controls.DataGrid. |
| xref:System.Windows.Controls.DataGridColumn.Width%2A?displayProperty=nameWithType | Sets a specific width for an individual column. Overrides xref:System.Windows.Controls.DataGrid.ColumnWidth%2A?displayProperty=nameWithType. |
By default, xref:System.Windows.Controls.DataGrid column headers are displayed. To hide column headers, the xref:System.Windows.Controls.DataGrid.HeadersVisibility%2A property must be set to xref:System.Windows.Controls.DataGridHeadersVisibility.Row?displayProperty=nameWithType or xref:System.Windows.Controls.DataGridHeadersVisibility.None?displayProperty=nameWithType. By default, when column headers are displayed, they automatically size to fit their content. The column headers can be given a specific height by setting the xref:System.Windows.Controls.DataGrid.ColumnHeaderHeight%2A?displayProperty=nameWithType property.
Users can resize xref:System.Windows.Controls.DataGrid rows and columns by dragging the row or column header dividers. The xref:System.Windows.Controls.DataGrid also supports automatic resizing of rows and columns by double-clicking the row or column header divider. To prevent a user from resizing particular columns, set the xref:System.Windows.Controls.DataGridColumn.CanUserResize%2A?displayProperty=nameWithType property to false for the individual columns. To prevent users from resizing all columns, set the xref:System.Windows.Controls.DataGrid.CanUserResizeColumns%2A?displayProperty=nameWithType property to false. To prevent users from resizing all rows, set the xref:System.Windows.Controls.DataGrid.CanUserResizeRows%2A?displayProperty=nameWithType property to false.
- xref:System.Windows.Controls.DataGrid
- xref:System.Windows.Controls.DataGridColumn
- xref:System.Windows.Controls.DataGridLength
- xref:System.Windows.Controls.DataGridLengthConverter