C#连接MYSQL数据库,包括增删查改!
public class DBLINK
{
public MySqlConnection GetConn()
{
MySqlConnection mysqlconn = new MySqlConnection("server=localhost;pwd=123;user=root;database=pfms;charset='gb2312'");//1,服务器 2 Mysql的密码 3 mysql的用户名 4 数据库名 5 数据库编码方式
return mysqlconn;
}
}
public class SQLEXQ : DBLINK
{
/// 查询操作
public DataTable Select(string sql)
{
MySqlConnection mysqlconn = null;
MySqlDataAdapter sda = null;
DataTable dt = null;
try
{
mysqlconn = base.GetConn();
sda = new MySqlDataAdapter(sql, mysqlconn);
dt = new DataTable();
sda.Fill(dt);
return dt;
}
catch (Exception)
{
throw;
}
}
/// 增操作
public int Add(string sql)
{
MySqlConnection conn = null;
MySqlCommand cmd = null;
try
{
conn = base.GetConn();
conn.Open();
cmd = new MySqlCommand(sql, conn);
int i = cmd.ExecuteNonQuery();
conn.Close();
return i;
}
catch (Exception)
{
throw;
}
}
// 修改
public int Change(string sql)
{
MySqlConnection conn = null;
MySqlCommand cmd = null;
try
{
conn = base.GetConn();
conn.Open();
cmd = new MySqlCommand(sql, conn);
int i = cmd.ExecuteNonQuery();
conn.Close();
return i;
}
catch (Exception)
{
throw;
}
}
//删除
public int Delete(string sql)
{
MySqlConnection conn = null;
MySqlCommand cmd = null;
try
{
conn = base.GetConn();
conn.Open();
cmd = new MySqlCommand(sql, conn);
int i = cmd.ExecuteNonQuery();
conn.Close();
return i;
}
catch (Exception)
{
throw;
}
}
}
}
具体使用方法:
//查询
string sql1 = "select max(inumber)+1 as num from income ";//查询sql语句
DataTable dt = mysql.Select(sql1);//放到数据表里
if (dt.Rows.Count > 0)//是否有数据
{
for (int i = 0; i
{
ia.textBox_bh.Text = dt.Rows[i]["num"].ToString();//显示到编辑框中
}
}
其他类似,只要把sql语句换一下,就OK了!for里边是做具体的操作,把数据读出来,放到哪里,或者删除,或者修改,你做主!
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