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  • c#中高效的excel导入sqlserver的方法

    将oledb读取的excel数据快速插入的sqlserver中,很多人通过循环来拼接sql,这样做不但容易出错而且效率低下,最好的办法是使用bcp,也就是System.Data.SqlClient.SqlBulkCopy 类来实现。不但速度快,而且代码简单,下面测试代码导入一个6万多条数据的sheet,包括读取(全部读取比较慢)在我的开发环境中只需要10秒左右,而真正的导入过程只需要4.5秒。


    using System;
    using System.Data;
    using System.Windows.Forms;
    using System.Data.OleDb;
    namespace WindowsApplication2
    {
        public partial class Form1 : Form
        {
            public Form1()
            {
                InitializeComponent();
            }

            private void button1_Click(object sender, EventArgs e)
            {
                //测试,将excel中的sheet1导入到sqlserver中
                string connString = "server=localhost;uid=sa;pwd=sqlgis;database=master";
                System.Windows.Forms.OpenFileDialog fd = new OpenFileDialog();
                if (fd.ShowDialog() == DialogResult.OK)
                {
                    TransferData(fd.FileName, "sheet1", connString);
                }
            }

            public void TransferData(string excelFile, string sheetName, string connectionString)
            {
                DataSet ds = new DataSet();
                try
                {
                    //获取全部数据
                    string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + excelFile + ";" + "Extended Properties=Excel 8.0;";
                    OleDbConnection conn = new OleDbConnection(strConn);
                    conn.Open();
                    string strExcel = "";
                    OleDbDataAdapter myCommand = null;
                    strExcel = string.Format("select * from [{0}$]", sheetName);
                    myCommand = new OleDbDataAdapter(strExcel, strConn);
                    myCommand.Fill(ds, sheetName);

                    //如果目标表不存在则创建
                    string strSql = string.Format("if object_id('{0}') is null create table {0}(", sheetName);
                    foreach (System.Data.DataColumn c in ds.Tables[0].Columns)
                    {
                        strSql += string.Format("[{0}] varchar(255),", c.ColumnName);
                    }
                    strSql = strSql.Trim(',') + ")";

                    using (System.Data.SqlClient.SqlConnection sqlconn = new System.Data.SqlClient.SqlConnection(connectionString))
                    {
                        sqlconn.Open();
                        System.Data.SqlClient.SqlCommand command = sqlconn.CreateCommand();
                        command.CommandText = strSql;
                        command.ExecuteNonQuery();
                        sqlconn.Close();
                    }
                    //用bcp导入数据
                    using (System.Data.SqlClient.SqlBulkCopy bcp = new System.Data.SqlClient.SqlBulkCopy(connectionString))
                    {
                        bcp.SqlRowsCopied += new System.Data.SqlClient.SqlRowsCopiedEventHandler(bcp_SqlRowsCopied);
                        bcp.BatchSize = 100;//每次传输的行数
                        bcp.NotifyAfter = 100;//进度提示的行数
                        bcp.DestinationTableName = sheetName;//目标表
                        bcp.WriteToServer(ds.Tables[0]);
                    }
                }
                catch (Exception ex)
                {
                    System.Windows.Forms.MessageBox.Show(ex.Message);
                }

            }

            //进度显示
            void bcp_SqlRowsCopied(object sender, System.Data.SqlClient.SqlRowsCopiedEventArgs e)
            {
                this.Text = e.RowsCopied.ToString();
                this.Update();
            }


        }
    }

    上面的TransferData基本可以直接使用,如果要考虑周全的话,可以用oledb来获取excel的表结构,并且加入ColumnMappings来设置对照字段,这样效果就完全可以做到和sqlserver的dts相同的效果了。

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  • 原文地址:https://www.cnblogs.com/wwwzzg168/p/3571991.html
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