DxSpinEdit<T>.ValueChanging Event
Fires when a user is changing the Spin Edit’s value. Use this event to validate/cancel user input.
Namespace: DevExpress.Blazor
Assembly: DevExpress.Blazor.v25.2.dll
NuGet Package: DevExpress.Blazor
Declaration
[Parameter]
public Action<ParameterValueChangingEventArgs<T>> ValueChanging { get; set; }
Event Data
The ValueChanging event's data class is ParameterValueChangingEventArgs<T>. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| NewValue | Gets or sets the new value being assigned to the parameter. |
| OldValue | Gets the current parameter value. |
Remarks
The ValueChanging event fires before a new value is applied to the editor (before the ValueChanged event). You can use this event to validate/cancel user input.
The following code snippet automatically formats numbers and handles the ValueChanging event to limit the value range (1 - 100). The current value is updated via two-way binding (@bind-Value).
<DxSpinEdit @bind-Value="@Amount"
ValueChanging="@OnValueChanging"
DisplayFormat="N0">
</DxSpinEdit>
<div class="mt-2">
<span>Current amount: @Amount</span>
</div>
@code {
int Amount { get; set; } = 50;
private void OnValueChanging(ParameterValueChangingEventArgs<int> e) {
if (e.NewValue < 1 || e.NewValue > 100) {
e.NewValue = e.OldValue;
}
}
}
Note
The Spin Edit also supports numeric masks that allow you to define the input format.