using system.data.sql
using system.data.sqlclient
dataset ds= new dataset();
string connectionString=连接字符串
string commandString=查询语句(如"select * from 表 where 内容=‘"+ textbox.text +"‘")
SqlConnection con= new SqlConnection(connectionString)
con.open()
SqlDataAdapter da= new SqlDataAdapter(commandString)
da.fill(ds)
datagrid.datesource=ds.table[0].defaultview