Native Events in Blazor Numeric TextBox Component

18 Jan 20222 minutes to read

This section explains the steps to include native events and pass data to event handler in the NumericTextBox component.

Bind native events to NumericTextBox

You can access any native event by using on <event> attribute with a component. The attribute’s value is treated as an event handler.

In the following example, the KeyPressed method is called every time the key is pressed on input.

@using Syncfusion.Blazor.Inputs

<SfNumericTextBox TValue="int?" @onkeypress='@KeyPressed'></SfNumericTextBox>

@code {
    public void KeyPressed(){
      Console.WriteLine("Key Pressed!");

Also, you can rewrite the previous example code as follows using Lambda expressions.

@using Syncfusion.Blazor.Inputs

<SfNumericTextBox TValue="int?" @onkeypress="@(() => Console.WriteLine("Key Pressed!"))"></SfNumericTextBox>

Pass event data to event handler

Blazor provides set of argument types to map to native events. The list of event types and event arguments are:

  • Focus Events - FocusEventArgs
  • Mouse Events - MouseEventArgs
  • Keyboard Events - KeyboardEventArgs
  • Input Events - ChangeEventArgs/EventArgs
  • Touch Events – TouchEventArgs
  • Pointer Events – PointerEventArgs

In the following example, the KeyPressed method is called every time any key is pressed inside input. But the message will be printed when you press “n” key.

@using Syncfusion.Blazor.Inputs

<SfNumericTextBox TValue="int?" @onkeypress='@(e => KeyPressed(e))'></SfNumericTextBox>

@code {
    public void KeyPressed(KeyboardEventArgs args)
        if (args.Key == "5")
            Console.WriteLine("5 was pressed");

Using Lambda expression also, you can pass the event data to the event handler.

List of Native events supported

List of Native events        
onclick onblur onfocus onfocusout  
onmousemove onmouseover onmouseout onmousedown onmouseup
ondblclick onkeydown onkeyup onkeypress  
ontouchend onfocusin onmouseup ontouchstart