.NET 7

Executing async operations onchange in Blazor

calendar_today 10 January 2023 07:35

ASP.NET Core Blazor .NET 7

Blazor's two-way databinding model is extremely powerful, but sometimes it can get in the way of what you want to do. For example, you might want to execute an asynchronous operation such as remote validation when a value changes in a textbox. Perhaps you want to check instantaneously that the value - a username maybe - doesn't already exist in a database before you accept a new registration. You cannot add an onchange event handler if you already have a value bound to the element, so what can you do? In this article, I look at solutions for both HTML elements and EditForm input validation components up to an including .NET 7, and a new feature released in .NET 7.0.1.