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Question

我正在上传Excel文件并将数据插入SQL Server。但问题是，在将Excel数据发送到SQL Server之前，我想在发送之前添加额外的列和值。

这是我尝试过的代码：

using (OleDbConnection exel_con = new OleDbConnection(conString))
{
    exel_con.Open();
    string sheet1 = exel_con.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null).Rows[0]["TABLE_NAME"].ToString();

    DataTable dtExcelData = new DataTable();
    //[OPTIONAL]: It is recommended as otherwise the data will be considered as String by default.
    dtExcelData.Columns.AddRange(new DataColumn[12] { new DataColumn("Full Name", typeof(string)),
                    new DataColumn("Email Address", typeof(string)),
                    new DataColumn("ID Type",typeof(string)),
                    new DataColumn("ID Number", typeof(string)),
                    new DataColumn("Gender",typeof(string)),
                    new DataColumn("Date of Birth", typeof(DateTime)),
                    new DataColumn("Nationality",typeof(string)),
                    new DataColumn("Married Status", typeof(string)),
                    new DataColumn("Join Date", typeof(DateTime)),
                    new DataColumn("Position",typeof(string)),
                    new DataColumn("Salary/Wages Frequency", typeof(string)),
                    new DataColumn("Salary/Wages Amount",typeof(int))
    });

    // Where I tried to add new column
    dtExcelData.Columns.Add("AdminId", typeof(int));

    foreach (DataRow row in dtExcelData.Rows)
    {
        // Where I tried to add new value to the column.
        row["AdminId"] = 1;
    }

    using (OleDbDataAdapter oda = new OleDbDataAdapter("SELECT * FROM [" + sheet1 + "]", exel_con))
    {
        oda.Fill(dtExcelData);
    }

    exel_con.Close();

    string consString = ConfigurationManager.ConnectionStrings["PayrollSystem"].ConnectionString;

    using (SqlConnection con = new SqlConnection(consString))
    {
        using (SqlBulkCopy sqlBulkCopy = new SqlBulkCopy(con))
        {
            // Set the database table name
            sqlBulkCopy.DestinationTableName = "dbo.Employee";

            //[OPTIONAL]: Map the Excel columns with that of the database table
            sqlBulkCopy.ColumnMappings.Add("AdminId", "AdminId");
            sqlBulkCopy.ColumnMappings.Add("Full Name", "FullName");
            sqlBulkCopy.ColumnMappings.Add("Email Address", "Email");
            sqlBulkCopy.ColumnMappings.Add("ID Type", "IdType");
            sqlBulkCopy.ColumnMappings.Add("ID Number", "IdNumber");
            sqlBulkCopy.ColumnMappings.Add("Gender", "Gender");
            sqlBulkCopy.ColumnMappings.Add("Date of Birth", "DateOfBirth");
            sqlBulkCopy.ColumnMappings.Add("Nationality", "Nationality");
            sqlBulkCopy.ColumnMappings.Add("Married Status", "MaritalStatus");
            sqlBulkCopy.ColumnMappings.Add("Join Date", "JoinDate");
            sqlBulkCopy.ColumnMappings.Add("Position", "Position");
            sqlBulkCopy.ColumnMappings.Add("Salary/Wages Frequency", "SalaryFrequency");
            sqlBulkCopy.ColumnMappings.Add("Salary/Wages Amount", "SalaryAmount");

            con.Open();
            sqlBulkCopy.WriteToServer(dtExcelData);
            con.Close();
        }
    }
}

请高度赞赏任何帮助解决这个问题。

Answer 1

您应该在Fill() DataTable之后将值添加到新列。在填写之前，它没有任何行可循环使用。

实际上，在填充DataTable之后应该添加新列，因为您要使用SELECT *来填充它，因此Excel中的列必须与DataTable中的列匹配。

因此，首先填写DataTable。然后添加新列和值。