Question

我在代码背后写道。但Viewbag.message将在警告消息中显示null .myvar是一个变量。我使用断点，myvar将由Viewbag.message正确设置。但它会在警报中显示为空。

         <script src="~/Scripts/jquery-1.7.1.js"></script>
         <script src="~/Scripts/jquery.unobtrusive-ajax.js"></script>

   @{string myvar = ViewBag.AlertMessage;}

   @using (Ajax.BeginForm("action", "controller", new AjaxOptions { HttpMethod = "Post",    OnSuccess = "Messsage" }))
                   {

  <script type="text/javascript">

   function Messsage() {

    alert('@ViewBag.AlertMessage');    //infact, it shows alert('');
    }


  </script>

Answer 1

是在控制器操作中定义的ViewBag.AlertMessage吗？

您可以通过

替换数据

@{string myvar = "hello there !";}

<script type="text/javascript">
    function Messsage() {
        alert('@myvar');    // should show "hello there"
    }
</script>

或在结果

后面的操作方法中定义您的viewbag项目

public ActionResult Index() {
    ViewBag.AlertMessage = "hello there !"
    return View();
}

Answer 2

<script type="text/javascript">
function Messsage() {
    alert('@myvar');    // should show "hello there"
}
</script>
 @using (Ajax.BeginForm("AjaxAction", "Home", new AjaxOptions { HttpMethod = "Post", OnSuccess = "Messsage" }))
{

    <script type="text/javascript">
        function Messsage() {

            alert("@ViewBag.AjaxMessage");
        }
    </script>

    <input type="submit" value="Submit" />

}

Answer 3

尝试在控制器操作中设置ViewBag.AlertMessage的值，该操作返回已定义Ajax.Begin表单的视图。

例如

 public class HomeController : Controller
    {
        public ActionResult Index()
        {
            ViewBag.Message = "Modify this template to jump-start your ASP.NET MVC application.";
            ViewBag.AlertMessage = "AjaxMessage.";

            return View();
        }
     }

在索引视图上我已经放置了以下代码，在Home Controller上调用了AjaxAction。

  @using (Ajax.BeginForm("AjaxAction", "Home", new AjaxOptions { HttpMethod = "Post", OnSuccess = "Messsage" }))
    {

        <script type="text/javascript">
            function Messsage() {

                alert("@ViewBag.AjaxMessage");
            }
        </script>

        <input type="submit" value="Submit" />

    }

Viewbag在警报中为空

3 个答案: