blazor-devexpress-dot-blazor-dot-dxgriddatacolumn-520638d5.md
Indicates that the column is unbound and specifies its data type.
Namespace : DevExpress.Blazor
Assembly : DevExpress.Blazor.v25.2.dll
NuGet Package : DevExpress.Blazor
[DefaultValue(GridUnboundColumnType.Bound)]
[Parameter]
public GridUnboundColumnType UnboundType { get; set; }
| Type | Default | Description |
|---|---|---|
| GridUnboundColumnType | Bound |
An enumeration value.
|
Available values:
| Name | Description |
|---|---|
| Bound |
The column is bound to a data field. This field specifies the column data type.
| | Integer |
The column contains Int32 values.
| | Decimal |
The column contains Decimal values.
| | DateTime |
The column contains DateTime values.
| | String |
The column contains String values.
| | Boolean |
The column contains Boolean values.
| | Object |
The column contains Object values.
|
To create an unbound column, add a DxGridDataColumn object to the Columns collection and specify the column’s UnboundType and FieldName properties. The FieldName property value should be unique and should not match field names in the Grid’s data source.
You can use the following API to obtain column values:
UnboundExpressionSpecifies an expression to evaluate values for the unbound column. An expression might consist of field names, constants, operators, and functions.UnboundColumnDataAllows you to implement custom logic or obtain column values from a custom/external data source.
<DxGrid Data="forecasts" UnboundColumnData="Grid_CustomUnboundColumnData">
<Columns>
<DxGridDataColumn FieldName="Date" Caption="Date" />
<DxGridDataColumn FieldName="TemperatureC" Caption="@("Temperature (\x2103)")" />
<DxGridDataColumn FieldName="TemperatureF" Caption="@("Temperature (\x2109)")"
UnboundType="GridUnboundColumnType.Decimal"
UnboundExpression="32 + [TemperatureC] / 0.5556" />
<DxGridDataColumn FieldName="Summary"
UnboundType="GridUnboundColumnType.String" />
</Columns>
</DxGrid>
@code {
private WeatherForecast[]? forecasts;
protected override async Task OnInitializedAsync() {
forecasts = await ForecastService.GetForecastAsync(DateTime.Now);
}
void Grid_CustomUnboundColumnData(GridUnboundColumnDataEventArgs e) {
if (e.FieldName == "Summary") {
int temperature = Convert.ToInt32(e.GetRowValue("TemperatureC"));
e.Value = GetTemperatureString(temperature);
}
}
static string GetTemperatureString(int value) {
if (value < -10)
return "Cool";
if (value >= -10 && value < 5)
return "Chilly";
if (value >= 5 && value < 15)
return "Warm";
return "Hot";
}
}
View Example: Create and Edit Unbound Columns
See Also