PreventDefault on Blazor input
Ok, this is a bit dirty tricky: remove the last char to override user input key:
<input type="text"
value="@PetitionInput"
onkeydown="@PetitionHandleKeyDown"
onkeyup="@PetitionHandleKeyUp"
/>
// ...
private int _petitionCharStep = 0;
private string _petition = "This is a dummy text";
public string PetitionInput { get; set; } = string.Empty;
void PetitionHandleKeyDown(UIKeyboardEventArgs arg) {
if (_petitionCharStep >= _petition.Length )
{
PetitionInput = _petition.Substring(0, _petition.Length-1 );
_petitionCharStep--;
}
}
void PetitionHandleKeyUp(UIKeyboardEventArgs arg) {
if (_petitionCharStep < _petition.Length )
{
PetitionInput += _petition[_petitionCharStep];
_petitionCharStep++;
}
}
Test it at blazorfiddle.
You can think a little differently in Blazor.
Rather than using "bind" and preventing the keystroke, you can set the "value" and handle the "oninput" event, like this:
https://blazorfiddle.com/s/azdn892n
@page "/"
<h1>Start typing something...</h1>
<input type="text" value="@PetitionInput" oninput="@PetitionHandleKeyDown" />
@functions {
private int _petitionCharStep = 0;
private string _petition = "This is a dummy text";
public string PetitionInput { get; set; } = string.Empty;
void PetitionHandleKeyDown(UIChangeEventArgs arg) {
PetitionInput = _petition.Substring(0,++_petitionCharStep);
Console.WriteLine(PetitionInput);
}
}
I can't imagine why you would want to do this, and there are many extra things you need to do to cover backspaces, arrow keys, tab etc...