C#连接数据库的方法

SqlConnection conn = new SqlConnection(connstr); conn.Open();

return conn; }

public static int ExecuteNonQuery(string cmdText, params SqlParameter[] parameters)//注意看有使用长度可变参数进行了简化

{ using (SqlConnection conn = new SqlConnection(connstr))

{ conn.Open();

return ExecuteNonQuery(conn, cmdText, parameters); }

} public static object ExecuteScalar(string cmdText,

params SqlParameter[] parameters) {

using (SqlConnection conn = new SqlConnection(connstr)) {

conn.Open(); return ExecuteScalar(conn, cmdText, parameters);

} }

public static DataTable ExecuteDataTable(string cmdText, params SqlParameter[] parameters)

{ using (SqlConnection conn = new SqlConnection(connstr))

{ conn.Open();

return ExecuteDataTable(conn, cmdText, parameters); }

} public static int ExecuteNonQuery(SqlConnection conn,string cmdText,

params SqlParameter[] parameters) {

using (SqlCommand cmd = conn.CreateCommand()) {