C#上位机连接数据库SQL,已经可以建立数据库名称,可以添加表的名称,可以添加数据,但是读取显示的时候会报"Unable to connect to any of the specified MySQL hosts"这个错误?
string ConStr = "Data Source = admin-PC; Database = Celou;"
+ "User Id = sa; Password = 123456";
SqlConnection SqlCon = new SqlConnection(ConStr.ToString());
try
{
SqlCon.Open();
MessageBox.Show("数据库已连接");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
上面这个都能连接成功
下面这个就报错
为啥呢?
public void ConnectView()
{
string ConStr = "Data Source = admin-PC; Database = Celou;"
+ "User Id = sa; Password = 123456";
MySqlConnection conn = new MySqlConnection(ConStr); //新建连接
try
{
conn.Open();
MessageBox.Show("已经建立连接");
string sqlCmd = "select * from information_demo"; //from后面的是自己创建的表
MySqlCommand cmd = new MySqlCommand(sqlCmd, conn);
MySqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
int index = this.dataGridView1.Rows.Add();
this.dataGridView1.Rows[index].Cells[0].Value = reader.GetString("ID");
this.dataGridView1.Rows[index].Cells[1].Value = reader.GetString("时间");
this.dataGridView1.Rows[index].Cells[2].Value = reader.GetString("产品型号");
this.dataGridView1.Rows[index].Cells[3].Value = reader.GetString("二维码");
this.dataGridView1.Rows[index].Cells[4].Value = reader.GetString("组号");
this.dataGridView1.Rows[index].Cells[5].Value = reader.GetString("测试压力");
this.dataGridView1.Rows[index].Cells[6].Value = reader.GetString("测试值");
this.dataGridView1.Rows[index].Cells[7].Value = reader.GetString("测试结果");
}
}
catch (MySqlException ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}