如何从C#背后的代码添加JavaScript？

string script = "alert('Hello, JavaScript!');";
ClientScript.RegisterStartupScript(this.GetType(), "MyScript", script, true);

ViewBag.Message = "Hello, JavaScript!";

<script>
    var message = '@ViewBag.Message';
    alert(message);
</script>

@inject IJSRuntime JSRuntime

<button @onclick="CallJavaScript">Call JavaScript</button>

@code {
    private async Task CallJavaScript()
    {
        await JSRuntime.InvokeVoidAsync("alert", "Hello, JavaScript!");
    }
}