ASP.NET MVC：一个Excel工作表，使用ASP.NET MVC将此数据插入到SQL Server表中

Question

Insert excel data into sql server table using ASP.NET MVC. Error in in controller on this line: products.WriteToServer(_product);

this is error message :

The given value of type String from the data source cannot be converted to type int of the specified target column.

controller code:

  [HttpPost]
        public ActionResult Index(HttpPostedFileBase postedFile)
        {
            string filePath = string.Empty;
            if (postedFile != null)
            {
                string path = Server.MapPath("~/Uploads/");
                if (!Directory.Exists(path))
                {
                    Directory.CreateDirectory(path);
                }

                filePath = path + Path.GetFileName(postedFile.FileName);
                string extension = Path.GetExtension(postedFile.FileName);
                postedFile.SaveAs(filePath);

                string conString = string.Empty;
                switch (extension)
                {
                    case ".xls": //Excel 97-03.
                        conString = ConfigurationManager.ConnectionStrings["Excel03ConString"].ConnectionString;
                        break;
                    case ".xlsx": //Excel 07 and above.
                        conString = ConfigurationManager.ConnectionStrings["Excel07ConString"].ConnectionString;
                        break;
                }

                DataTable dt = new DataTable();
             //   DataTable _dt = new DataTable();

               // DataTable optionCategories = new DataTable();
               // DataTable options = new DataTable();
                DataTable _product = new DataTable();
                conString = string.Format(conString, filePath);

                using (OleDbConnection connExcel = new OleDbConnection(conString))
                {
                    using (OleDbCommand cmdExcel = new OleDbCommand())
                    {
                        using (OleDbDataAdapter odaExcel = new OleDbDataAdapter())
                        {
                            cmdExcel.Connection = connExcel;

                            //Get the name of First Sheet.
                            connExcel.Open();
                            DataTable dtExcelSchema;
                            dtExcelSchema = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                            string sheetName = dtExcelSchema.Rows[0]["TABLE_NAME"].ToString();
                          //  string sheetName1 = dtExcelSchema.Rows[1]["TABLE_NAME"].ToString();
                            connExcel.Close();

                            //Read Data from First Sheet.
                            connExcel.Open();
                            cmdExcel.CommandText = "SELECT * From [" + sheetName + "]";

                            odaExcel.SelectCommand = cmdExcel;
                            odaExcel.Fill(_product);
                            // cmdExcel.CommandText = "SELECT * From [" + sheetName1 + "]";
                            //odaExcel.Fill(_dt);
                            connExcel.Close();
                        }
                    }
                }

                conString = ConfigurationManager.ConnectionStrings["Constring"].ConnectionString;
                using (SqlConnection con = new SqlConnection(conString))
                 {
                    using (SqlBulkCopy products = new SqlBulkCopy(con))
                    {
                        //Set the database table name.
                        products.DestinationTableName = "dbo.Products";


                        // [OPTIONAL]: Map the Excel columns with that of the database table
                        products.ColumnMappings.Clear();
                        products.ColumnMappings.Add("Id", "Id");
                        products.ColumnMappings.Add("Sku", "Sku");
                        products.ColumnMappings.Add("UPC", "UPC");
                        products.ColumnMappings.Add("Name", "Name");
                        products.ColumnMappings.Add("Price", "Price");
                        products.ColumnMappings.Add("CostPrice", "CostPrice");
                        products.ColumnMappings.Add("RetailPrice", "RetailPrice");
                      products.ColumnMappings.Add("SalePrice", "SalePrice");
                        products.ColumnMappings.Add("Weight", "Weight");
                        products.ColumnMappings.Add("Quantity", "Quantity");
                        products.ColumnMappings.Add("Description", "Description");
                        products.ColumnMappings.Add("Keywords", "Keywords");
                        products.ColumnMappings.Add("TaxClassId", "TaxClassId");
                        products.ColumnMappings.Add("IsFeatured", "IsFeatured");
                        products.ColumnMappings.Add("IsVisible", "IsVisible");
                        products.ColumnMappings.Add("AddQuantity", "AddQuantity");
                        products.ColumnMappings.Add("IsCustomOptionProduct", "IsCustomOptionProduct");
                       // products.ColumnMappings.Add("DrowingRefNo", "DrowingRefNo");    
                        con.Open();
                        products.WriteToServer(_product);

                        con.Close();
                    }

                }
            }

            return View();
        }
    }
}

---------sql server table script----------

CREATE TABLE [dbo].[Products](
    [Id] [int] IDENTITY(1,1) NOT NULL,
    [Sku] [nvarchar](100) NULL,
    [UPC] [nvarchar](max) NULL,
    [Name] [nvarchar](1000) NOT NULL,
    [Price] [decimal](18, 2) NOT NULL,
    [CostPrice] [decimal](18, 2) NULL,
    [RetailPrice] [decimal](18, 2) NULL,
    [SalePrice] [decimal](18, 2) NULL,
    [Weight] [decimal](18, 2) NOT NULL,
    [Quantity] [int] NULL,
    [Description] [nvarchar](max) NULL,
    [Keywords] [nvarchar](2000) NULL,
    [TaxClassId] [int] NULL,
    [IsFeatured] [bit] NOT NULL,
    [IsVisible] [bit] NOT NULL,
    [AddQuantity] [int] NULL,
    [IsCustomOptionProduct] [bit] NOT NULL DEFAULT ((0)),
 CONSTRAINT [PK_dbo.Products] PRIMARY KEY CLUSTERED 
(
    [Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]

GO

ALTER TABLE [dbo].[Products]  WITH CHECK ADD  CONSTRAINT [FK_dbo.Products_dbo.TaxClasses_TaxClassId] FOREIGN KEY([TaxClassId])
REFERENCES [dbo].[TaxClasses] ([Id])
GO

ALTER TABLE [dbo].[Products] CHECK CONSTRAINT `enter code here`[FK_dbo.Products_dbo.TaxClasses_TaxClassId]
GO

Answer 1

suggestion change column datatype like as below , where you are expecting datatype to be integer

 Convert.ToInt32(dt.Columns["Product"]);

---

I suggest you create datatable in you code with propert types of your column and copy each row of datatable you are receiving from excelt to stongly type datatable.