Make a catching error using SweetAlert in ASP.NET MVC

Question

I have controller that do a try catch when uploading like this :

try
{
    connExcel.Open();
    cmdExcel.CommandText = "SELECT NAMA , REPLACE(NOHP, '-', '' ) as NOHP,TANGGAL, NOMINAL  From [" + sheetName +
                           "] WHERE NAMA IS NOT NULL OR NoHP IS NOT NULL OR Tanggal IS NOT NULL OR NOMINAL IS NOT NULL";

    odaExcel.SelectCommand = cmdExcel;

    // dapetin data dimasukin ke dtSheet
    odaExcel.Fill(dtSheet);
    connExcel.Close();
}
catch (Exception)
{
    //here the Sweetalert or just alert
}

I want to make a sweetalert2 popup that said "the template is not match" when not meet the try condition.

What should I do? I have installed swal library in _layout too, because I used it in JS Ajax before, but still confused with this case.

The whole action:

[HttpPost]
public ActionResult Index(HttpPostedFileBase postedFile)
{
        var path = Server.MapPath("~/Uploads/");
        var filePath = string.Empty;
        var extension = string.Empty;
        var dtSheet = new DataTable();
        var ExcelData = new DataSet();
        var user = User.Identity.Name;
        var prefix = user + DateTime.Now.ToString("yyyyMMddHHmmss");

        if (postedFile != null)
        {
            if (!Directory.Exists(path)) 
                Directory.CreateDirectory(path);

            filePath = path + Path.GetFileName(postedFile.FileName.Replace(postedFile.FileName,prefix));
            extension = Path.GetExtension(postedFile.FileName);
            postedFile.SaveAs(filePath+extension);
        }

        if (postedFile == null) 
            return new EmptyResult();

        var connectionString = string.Empty;

        //milih constring tergantung file
        switch (extension)
        {
            case ".xls": //<= 2003 version
                connectionString = ConfigurationManager.ConnectionStrings["Excel03ConString"].ConnectionString;
                break;

            case ".xlsx": //>= 2007 version
                connectionString = ConfigurationManager.ConnectionStrings["Excel07ConString"].ConnectionString;
                break;
        }

        //oledb koneksi
        connectionString = string.Format(connectionString, filePath+extension);

        using (var connExcel = new OleDbConnection(connectionString))
        {
            using (var cmdExcel = new OleDbCommand())
            {
                using (var odaExcel = new OleDbDataAdapter())
                {
                    cmdExcel.Connection = connExcel;
                    //ambil nama sheet #1
                    connExcel.Open();
                    DataTable dtExcelSchema;
                    dtExcelSchema = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                    var sheetName = dtExcelSchema.Rows[0]["TABLE_NAME"].ToString();
                    connExcel.Close();

                    try
                    {
                        connExcel.Open();
                        cmdExcel.CommandText =
                            "SELECT NAMA , REPLACE(NOHP, '-', '' ) as NOHP,TANGGAL, NOMINAL  From [" + sheetName +
                            "] WHERE NAMA IS NOT NULL OR NoHP IS NOT NULL OR Tanggal IS NOT NULL OR NOMINAL IS NOT NULL";
                        odaExcel.SelectCommand = cmdExcel;
                        //dapetin data dimasukin ke dtSheet
                        odaExcel.Fill(dtSheet);
                        connExcel.Close();
                    }
                    catch (Exception)
                    {
                        //here the Sweetalert or just alert
                    }
                }
            }
        }

        ExcelData.Tables.Add(dtSheet);
        return View(ExcelData);
}

Thanks :)

Answer 1

You can not return the sweetalert from controller. You have to set it up to view side. Here is example

try
{
    connExcel.Open();
    cmdExcel.CommandText = "SELECT NAMA , REPLACE(NOHP, '-', '' ) as NOHP,TANGGAL, NOMINAL  From [" + sheetName +
                           "] WHERE NAMA IS NOT NULL OR NoHP IS NOT NULL OR Tanggal IS NOT NULL OR NOMINAL IS NOT NULL";

    odaExcel.SelectCommand = cmdExcel;

    // dapetin data dimasukin ke dtSheet
    odaExcel.Fill(dtSheet);
    connExcel.Close();
}
catch (Exception)
{
    ViewBag.Message = "Your Message";
}

On html page in script tag.

<script>
    $(function() {
        var message = '@ViewBag.Message';
        if (message  != '')
            swal({ title: "Done", text: message , icon: "error" });

    });
</script>