Index
@page "/"
@using Microsoft.JSInterop
@inject IJSRuntime JS
@functions{
ElementReference TextAreaRef;
int lineNumber = 0;
string TextAreaText = "Keep clicking the button and watch the vertical scroll move down.\n";
void ScrollToEnd() {
lineNumber++;
TextAreaText += $"Line number {lineNumber}\n";
JS.InvokeVoidAsync("scrollToEnd", new object[] {TextAreaRef});
}
}
<p>
Demostrates how to call a JavaScript function from C# that scrolls a textarea to the end.
</p>
<button class="btn btn-primary m-2" @onclick="ScrollToEnd">Add Line</button>
<br/>
<textarea @ref=TextAreaRef value="@TextAreaText" class="form-control" rows="5"></textarea>
namespace BlazorFiddleProject
{
using Microsoft.AspNetCore.Components.Builder;
using Microsoft.Extensions.DependencyInjection;
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
}
public void Configure(IComponentsApplicationBuilder app)
{
app.AddComponent<App>("app");
}
}
}
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<meta name="viewport" content="width=device-width">
<title>BlazorFiddleProject</title>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
<style>
app { }
</style>
<script type="text/javascript">
function scrollToEnd(textarea) {
textarea.scrollTop = textarea.scrollHeight;
}
</script>
</head>
<body>
<app>Loading...</app>
<script src="_framework/blazor.webassembly.js"></script>
</body>
</html>
Add component
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