ValidationEventArgs.SetError(Object) Method

Marks the processed input value as invalid and displays an error within the editor.

Namespace: DevExpress.Xpf.Editors

Assembly: DevExpress.Xpf.Core.v24.1.dll

NuGet Package: DevExpress.Wpf.Core

Declaration

C#

public void SetError(
    object errorContent
)

VB.NET

Public Sub SetError(
    errorContent As Object
)

Parameters

Name	Type	Description
errorContent	Object	An object that specifies the error content.

Remarks

The SetError method automatically sets the ValidationEventArgs.IsValid property to false. If the errorContent parameter is set to an empty string or null, the ValidationEventArgs.IsValid property is set to true and the error isn’t displayed.

C#

private void textEdit_Validate(object sender, ValidationEventArgs e) {
    if(Convert.ToDouble(e.Value) < 0)
        e.SetError("Negative values are not allowed.");
}

VB.NET

Private Sub textEdit_Validate(ByVal sender As Object, ByVal e As ValidationEventArgs)
    If Convert.ToDouble(e.Value) < 0 Then
        e.SetError("Negative values are not allowed.")
    End If
End Sub

The image below shows the result:

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the SetError(Object) method.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

wpf-data-grid-validate-data-rows/CS/ValidateRow_CodeBehind/MainWindow.xaml.cs#L59

if(task.StartDate > task.EndDate)
    e.SetError("Start Date must be less than End Date");
if(string.IsNullOrEmpty(task.TaskName))

VB.NET

wpf-data-grid-validate-data-rows/VB/ValidateRow_CodeBehind/MainWindow.xaml.vb#L50

Dim task = CType(e.Row, Task)
If task.StartDate > task.EndDate Then e.SetError("Start Date must be less than End Date")
If String.IsNullOrEmpty(task.TaskName) Then e.SetError("Enter a task name")