大部分人都知道用oledb来读取数据到dataset,但是读取之后怎么处理dataset就千奇百怪了。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,System.Data.SqlClient.SqlBulkCopy 对于新手来说还是比较陌生的,这个就是传说中效率极高的bcp,6万多数
大部分人都知道用oledb来读取数据到dataset,但是读取之后怎么处理dataset就千奇百怪了。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,System.Data.SqlClient.SqlBulkCopy 对于新手来说还是比较陌生的,这个就是传说中效率极高的bcp,6万多数据从excel导入到sql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。
http://yrq205.blog.163.com/blog/static/47672140201162505927442/

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