asp.net-core - 如果值发生变化，如何调用选择列表中的函数或方法？

Question

我有一个场景，如果我更改选择列表的值，我希望能够清除模型或任何我想清除的值。是否可以在 select 标签助手中调用函数或方法？像这样:

<select asp-for="Input.DriverName" class="form-control"
                                asp-items="Model.DriverNotUser"
                               onchange="myfunction()">
</select>

Answer 1

调用 javascript 函数:

<select class="form-control" 
    asp-for="DriverName" 
    asp-items="Model.DriverNotUser" 
    onchange="myfunction();">
</select>

@section Scripts{
    function myfunction() {
        // Do whatever...
    }
}

要提交到后端，将选择列表放在一个表单中并调用提交:

<!-- submit to the OnGet() method -->
<!-- add method="post" to submit to the OnPost() method -->
<form>
    <select class="form-control" 
            asp-for="DriverName" 
            asp-items="Model.DriverNotUser" 
            onchange="this.form.submit();">
    </select>
</form>

在后端调用自定义方法:

<!-- submit to the OnPostMyMethod() method -->
<form method="post" asp-page-handler="MyMethod">
    <select class="form-control" 
            asp-for="DriverName" 
            asp-items="Model.DriverNotUser" 
            onchange="this.form.submit();">
    </select>
</form>

后端方法:

public IActionResult OnPostMyMethod()
{
    // ...
}