c#连接SQL数据库的使用方法

1、c#tc#t接SQLSQL数据库的使用方法最正确答案1 . 提取单条记录/using System.Data;/using System.Data.SqlClient;using (SqlConnection cn = new SqlConnection(%1)/ConfigurationManager.ConnectionStringsdb2ConnectionString.Connectio nString/Data Source=myServerAddress;Initial Catalog=myDataBase;UserId=myUsername;Password=myPassword

2、;SqlCommand cmd = new SqlCommand(Select Count(*) Fromjobs,cn);cn.Open();%2=cmd.ExecuteScalar(); /Message.InnerHtml 2 .单值比拟/using System.Data;/using System.Data.SqlClient;using (SqlConnection cn = new SqlConnection(%1)/ConfigurationManager.ConnectionStringsdb2ConnectionString.Connectio nString/Data S

3、ource=myServerAddress;Initial Catalog=myDataBase;UserId=myUsername;Password=myPassword;SqlCommand cmd = new SqlCommand(Select Count(*) Fromjobs,cn);cn.Open();%2=cmd.ExecuteScalar(); /Message.InnerHtmlif(%2=%3)%43 .显示表格/using System.Data;/using System.Data.SqlClient;DataSet ds=null;using (SqlConnecti

4、on cn = new SqlConnection(%1)/ConfigurationManager.ConnectionStringsdb2ConnectionString.Connectio nString/Data Source=myServerAddress;Initial Catalog=myDataBase;UserId=myUsername;Password=myPassword;cn.Open();cmd=new SqlDataAdapter(Select * From Author,cn);ds=new DataSet();cmd.Fill(ds,%2); / 作者 MyDa

5、taGrid.DataSource=ds.Tables(%2).DefaultView; / 作者 MyDataGrid.DataBind();4 .操作表格/using System.Data;/using System.Data.SqlClient;using (SqlConnection cn = new SqlConnection(%1)/ConfigurationManager.ConnectionStringsdb2ConnectionString.Connectio nString/Data Source=myServerAddress;Initial Catalog=myDat

6、aBase;UserId=myUsername;Password=myPassword;cn.Open();cmd=new SqlDataAdapter(Select * From Author,cn);ds=new DataSet();cmd.Fill(ds,%2); / 作者 MyDataGrid.DataSource=ds.Tables(%2).DefaultView; / 作者 MyDataGrid.DataBind();5 .数值范围查询/using System.Data;/using System.Data.SqlClient;using (SqlConnection cn =

7、new SqlConnection(%1)/ConfigurationManager.ConnectionStringsdb2ConnectionString.Connectio nString/Data Source=myServerAddress;Initial Catalog=myDataBase;UserId=myUsername;Password=myPassword;6 .关闭时断开连接/using System.Data;/using System.Data.SqlClient;using (SqlConnection cn = new SqlConnection(%1)/Con

8、figurationManager.ConnectionStringsdb2ConnectionString.Connectio nString/Data Source=myServerAddress;Initial Catalog=myDataBase;UserId=myUsername;Password=myPassword;7 .执行命令/using System.Data;/using System.Data.SqlClient;using (SqlConnection cn = new SqlConnection(%1)/ConfigurationManager.Connection

9、Stringsdb2ConnectionString.Connectio nString/Data Source=myServerAddress;Initial Catalog=myDataBase;UserId=myUsername;Password=myPassword;SqlCommand cmd = new SqlCommand(insert userRegister_tvalues(+ TextBox1.Text + , + TextBox2.Text + ),cn);cn.Open();cmd.ExecuteNonQuery();7.Oracle8/8i/9i 数据库(thin 模

10、式)/using System.Data;Oracle Set Your custom connection strings valuesODBCNew versionDriver=Microsoft ODBC forOracle;Server=myServerAddress;Uid=myUsername;Pwd=myPassword;Old versionDriver=Microsoft ODBC Driver forOracle;ConnectString=OracleServer.world;Uid=myUsername;Pwd=myPassw ord;OLE DB, OleDbConn

11、ection (.NET)Standard securityThis connection string uses a provider from Microsoft.Provider=msdaora;Data Source=MyOracleDB;UserId=myUsername;Password=myPassword;Standard SecurityThis connection string uses a provider from Oracle.Provider=OraOLEDB.Oracle;Data Source=MyOracleDB;UserId=myUsername;Pass

12、word=myPassword;Trusted ConnectionProvider=OraOLEDB.Oracle;Data Source=MyOracleDB;OSAuthent=1;OracleConnection (.NET)StandardData Source=MyOracleDB;Integrated Security=yes;This one works only with Oracle 8i release 3 or laterSpecifying username and passwordData Source=MyOracleDB;UserId=myUsername;Pa

13、ssword=myPassword;Integrated Security=no;This one works only with Oracle 8i release 3 or laterMissing the System.Data.OracleClient namespace? Download .NET ManagedProvider for Oracle Great article! Features of Oracle Data Provider for .NET by RamaMohan G. at C# Corner Omiting tnsnames.oraThis is ano

14、ther type of Oracle connection string that doesnt rely onyou to have a DSN for the connection. You create a connection stringbased on the format used in the tnsnames.ora file without the need toactually have one of these files on the client pc.SERVER=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=MyHost)

15、(PORT=MyPort)(CONNECT_DATA=(SERVICE_NAME=MyOracleSID);uid=myUsername;pwd=myPassword;Core Labs OraDirect (.NET)StandardUser ID=myUsername;Password=myPassword;Host=ora;Pooling=true;MinPool Size=0;Max Pool Size=100;Connection Lifetime=0;Read more at Core Lab And at the product page Data ShapeMS Data Sh

16、apeProvider=MSDataShape.1;Persist Security Info=False;DataProvider=MSDAORA;Data Source=orac;UserId=myUsername;Password=myPassword;16.程序计时DateTime runTime =Convert.ToDateTime(System.Configuration.ConfigurationSettings.AppSetting sTimerRunAt);/运行时间TimeSpan runTime = new TimeSpan(runTime.Ticks);/现在时间TimeSpan timeNow = new TimeSpan(DateTime.Now.Ticks);/时间间隔TimeSpan ts = runTime.Subtract(timeNow);/如果运行时间与当前时间的差大于0，那么任务执行时间为当日if(ts.TotalMilliseconds 0)return ts.TotalMilliseconds;/如果运行时间与当前时间的差小于0，那么任务执行时间为次日Else/差