在控制器中记录插入成功失败时如何显示消息或警报

Question

在我的_Layout.cshtml 页面中，有一个文本框允许用户输入他/她的电子邮件地址（这是用于新闻通讯）。如果输入的电子邮件地址存在，则不会插入数据库，如果不存在则插入数据库.同时，如果没有插入我想显示一条错误消息，如果插入我想显示成功消息。这就是我插入数据库的方式，

public ActionResult getNewsLetterMail(string N_id, string N_EmailAdd)
    {
        Session["Ealert"] = null;
        Random random = new Random();
        int idONe = random.Next(99, 999);
        int idTwo = random.Next(999, 9999);
        string middle = "menuka";
        string fullID = idONe.ToString() + middle + idTwo.ToString();
        var N_ID = fullID;
        var N_Email = N_EmailAdd;
        TourCenterDBEntities NewsLetterEntities = new TourCenterDBEntities();
        var existing = NewsLetterEntities.News_Letter.Where(l => l.N_Email == N_EmailAdd);
        Debug.WriteLine(existing.Count());
        if (existing.Count() == 0)
        {
            News_Letter NewsLetterDetails = new News_Letter();
            NewsLetterDetails.N_id = N_ID;
            NewsLetterDetails.N_Email = N_Email;
            NewsLetterEntities.News_Letter.Add(NewsLetterDetails);
            NewsLetterEntities.SaveChanges();
            //want to send success text
        }
        else
        {
            //want to send error text                  
        }
        return Json(new { });
    }

如果成功或错误，它会返回到相同的_Layout.csthml 页面。 我该怎么做。希望你能帮忙。

Answer 1

你可以使用。返回内容。

if (existing.Count() == 0)
    {
        News_Letter NewsLetterDetails = new News_Letter();
        NewsLetterDetails.N_id = N_ID;
        NewsLetterDetails.N_Email = N_Email;
        NewsLetterEntities.News_Letter.Add(NewsLetterDetails);
        NewsLetterEntities.SaveChanges();

        //return Content("Your information saved successfully");
        return new JavascriptResult { Script = "alert('Your information saved successfully');" };
    }
    else
    {
        //return Content("Already exist. Please choose another.");
        return new JavascriptResult { Script = "alert('Your information saved successfully');" };                  
    }

Answer 2

public ActionResult getNewsLetterMail(string N_id, string N_EmailAdd)
{
    Session["Ealert"] = null;
    Random random = new Random();
    int idONe = random.Next(99, 999);
    int idTwo = random.Next(999, 9999);
    string middle = "menuka";
    string fullID = idONe.ToString() + middle + idTwo.ToString();
    var N_ID = fullID;
    var N_Email = N_EmailAdd;
    TourCenterDBEntities NewsLetterEntities = new TourCenterDBEntities();
    var existing = NewsLetterEntities.News_Letter.Where(l => l.N_Email == N_EmailAdd);
    Debug.WriteLine(existing.Count());
    string myMessage="";
    if (existing.Count() == 0)
    {
        News_Letter NewsLetterDetails = new News_Letter();
        NewsLetterDetails.N_id = N_ID;
        NewsLetterDetails.N_Email = N_Email;
        NewsLetterEntities.News_Letter.Add(NewsLetterDetails);
        NewsLetterEntities.SaveChanges();
        myMessage="success";
    }
    else
    {
        myMessage="failed";                  
    }
    return Json(myMessage, JsonRequestBehavior.AllowGet);
}

在你看来。

$.post('@Url.Action("getNewsLetterMail", "yourControllerName")', { N_id: N_id, N_EmailAdd: N_EmailAdd }).done(function (data) {
 if (data == "success") {
                alert("Success!");                    
 }
 if( data== "failed")  {
                alert("Failed!");                    
 }
}

Answer 3

我没有经验，但我会尝试这样的事情： 在我的视图模型中，我会放 字符串信息 然后在我看来

 @Html.DisplayFor(m=>m.info)

在控制器中

if(existing){info="success"}

您必须将信息传递给控制器​​中的视图模型

Answer 4

public ActionResult getNewsLetterMail(string N_id, string N_EmailAdd)
{
    Session["Ealert"] = null;
    Random random = new Random();
    int idONe = random.Next(99, 999);
    int idTwo = random.Next(999, 9999);
    string middle = "menuka";
    string fullID = idONe.ToString() + middle + idTwo.ToString();
    var N_ID = fullID;
    var N_Email = N_EmailAdd;
    TourCenterDBEntities NewsLetterEntities = new TourCenterDBEntities();
    var existing = NewsLetterEntities.News_Letter.Where(l => l.N_Email == N_EmailAdd);
    Debug.WriteLine(existing.Count());
    string myMessage="";
    if (existing.Count() == 0)
    {
        News_Letter NewsLetterDetails = new News_Letter();
        NewsLetterDetails.N_id = N_ID;
        NewsLetterDetails.N_Email = N_Email;
        NewsLetterEntities.News_Letter.Add(NewsLetterDetails);
        NewsLetterEntities.SaveChanges();
        myMessage="success!";
    }
    else
    {
        myMessage="Failed!";                  
    }
    return Json(myMessage, JsonRequestBehavior.AllowGet);
}

在 Views 中，您可以添加 jquery 来显示消息。以下是在视图中检索消息的示例。您可以相应地编辑表单中的名称。

`<script type="text/javascript">
  $(document).ready(function () {
   $("#yourForm").submit(function (e) {
      e.preventDefault();
        var valid = $("#yourForm").valid();
        if (valid) {
           $.ajax({
            url: "/getNewsLetterMail",
            type: "POST",
            data: {
                   Name: $("#N_id").val(),
                   Email: $("#N_EmailAdd").val(),
                    },
                    success: function (data) {
                        alert(data);
                        reset();
                    }
                });
            }
        });
 });
</script>'