ValidateCellEventArgs.ErrorContent Property
Gets or sets the validation error description.
Namespace: DevExpress.Maui.DataGrid
Assembly: DevExpress.Maui.DataGrid.dll
NuGet Package: DevExpress.Maui.DataGrid
Declaration
public string ErrorContent { get; set; }
Property Value
Type | Description |
---|---|
String | The error description. |
Example
This example shows how to validate a new cell value when a user modified it in an in-place cell editor and moves focus to another cell.
The DataGridView instance is bound to a collection of orders, and its Quantity column allows users to enter positive numbers only. If a new cell value does not pass validation, an error message is displayed and the user cannot move focus to another cell until the error is corrected.
Follow the steps below to validate cell values:
- Specify Validation Rules
Subscribe to the DataGridView.ValidateCell event, and implement validation logic in the event handler.
Use the event parameter’s OldValue and NewValue properties to get the cell’s original and new value (the value that should be validated). The FieldName and RowHandle properties allow you to obtain the column and row that contain the cell whose value is being edited.
If a cell value fails validation, set theErrorContent
property to the string that describes the validation error. A user cannot move focus to another cell until the error is fixed and theErrorContent
string is empty. - Indicate Errors
Handle the DataGridView.ValidationError event to provide a response to entering invalid data (for example, show validation error message to users). This event parameter’s ValidationErrorEventArgs.ErrorContent property contains the error description assigned to theValidateCellEventArgs.ErrorContent
property in the ValidateCell event handler.
<dxg:DataGridView x:Name="grid" ItemsSource="{Binding Orders}"
ValidateCell="Grid_ValidateCell"
ValidationError="Grid_ValidationError">
<!-- ... -->
</dxg:DataGridView>
using Microsoft.Maui.Controls;
using DevExpress.Maui.DataGrid;
// ...
private void Grid_ValidateCell(object sender, ValidateCellEventArgs e) {
if (e.FieldName == "Quantity" && (decimal)e.NewValue <= 0)
e.ErrorContent = "The value must be positive.";
}
private void Grid_ValidationError(object sender, ValidationErrorEventArgs e) {
DisplayAlert("Input Error", e.ErrorContent, "OK");
}
See Also