c#窗体怎么与数据库连接

1.引入命名空间

using System.Data.SqlClient

2.创建数据库连接对象

SqlConnection对象名= new SqlConnection("server=.database=NewQQuid=sapwd=123456")

3.打开数据库连接

对象名.Open()

一：通过System.Data.OracleClient(需要安装Oracle客户端并配置tnsnames.ora)

1. 添加命名空间System.Data.OracleClient引用

2. using System.Data.OracleClient

3.

string connString = "User ID=IFSAPPPassword=IFSAPPData Source=RACE"

OracleConnection conn = new OracleConnection(connString)

try

{

conn.Open()

MessageBox.Show(conn.State.ToString())

}

catch (Exception ex)

{

ShowErrorMessage(ex.Message.ToString())

}

finally

{

conn.Close()

}

二：通过System.Data.OracleClient(需要安装Oracle客户端不需配置tnsnames.ora)

1. 添加命名空间System.Data.OracleClient引用

2. using System.Data.OracleClient

3.

string connString = "User ID=IFSAPPPassword=IFSAPPData Source=(DESCRIPTION = (ADDRESS_LIST= (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = RACE)))"

OracleConnection conn = new OracleConnection(connString)

try

{

conn.Open()

MessageBox.Show(conn.State.ToString())

}

catch (Exception ex)

{

ShowErrorMessage(ex.Message.ToString())

}

finally

{

conn.Close()

}

三：通过System.Data.OleDb和Oracle公司的驱动

1. 添加命名空间System.Data.OracleClient引用

2. using System.Data.OleDb

3.

string connString = "Provider=OraOLEDB.Oracle.1User ID=IFSAPPPassword=IFSAPPData Source=(DESCRIPTION = (ADDRESS_LIST= (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = RACE)))"

OleDbConnection conn = new OleDbConnection(connString)

try

{

conn.Open()

MessageBox.Show(conn.State.ToString())

}

catch (Exception ex)

{

ShowErrorMessage(ex.Message.ToString())

}

finally

{

conn.Close()

}

四：通过System.Data.OleDb和微软公司的Oracle驱动

1. 添加命名空间System.Data.OracleClient引用

2. using System.Data.OleDb

3.

string connString = "Provider=MSDAORA.1User ID=IFSAPPPassword=IFSAPPData Source=(DESCRIPTION = (ADDRESS_LIST= (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = RACE)))"

OleDbConnection cnn = new OleDbConnection(connString)

try

{

conn.Open()

MessageBox.Show(conn.State.ToString())

}

catch (Exception ex)

{

ShowErrorMessage(ex.Message.ToString())

}

finally

{

conn.Close()

}

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