C ＃ connect to MySQL database

Create a new one C# Class library , Used with MySQL Data to connect . Its main access mode is ：
After logging into the database , have access to SQL Statement to operate the database .
Including increase 、 Delete 、 Modification and query .

One 、 Class libraries to be imported

using MySql.Data.MySqlClient;
using System.Data;

Two 、 Main code

class mysqlDB
{
    
    // Database connection 
    // Just log in once , Pass the returned object into the following function 
    public MySqlConnection connetion(string server, string user, string passwd)
    {
    
        String conStr = string.Format("server={0};user id={1};password={2};database=userdata", server, user, passwd);
        MySqlConnection DBcon = new MySqlConnection();
        DBcon.ConnectionString = conStr;
        DBcon.Open();
        return DBcon;
    }

    // Database operation 
    // No need for extra calls 
    public MySqlCommand command(string sql, MySqlConnection DBconn)
    {
    
        MySqlCommand rt = new MySqlCommand(sql, DBconn);
        return rt;
    }
    
    // Database addition, deletion and modification 
    public int Exute(string sql, MySqlConnection DBconn)
    {
    
        // Returns the number of affected rows 
        return this.command(sql, DBconn).ExecuteNonQuery();
    }

    // adopt select Statement to query 
    public MySqlDataReader read(string sql, MySqlConnection DBconn)
    {
    
        // Database query 
        return this.command(sql, DBconn).ExecuteReader();
    }
}

3、 ... and 、 Call mode

Suppose I have a database called userdata, There is a table under the database data, Set as follows

id	name	class
INT	varchar	varchar

Inquire about

The query calls MySqlDataReader function .

// Database query function 
private Tu DBshow()
{
    
    mysqlDB mysql = new mysqlDB();
    string sql = "SELECT * FROM userdata.data;";
    //DBconn Is the variable returned after login 
    IDataReader dr = mysql.read(sql, DBconn);
    while (dr.Read())
    {
    
        string id, userName, Class;
        id = dr["id"].ToString();
        userName = dr["name"].ToString();
        Class = dr["class"].ToString();
        string[] str = {
     id, userName, C88lass };
        this.DataGridView1.Rows.Add(str);
    }
    dr.Close();
}

Additions and deletions

Including but not limited to addition, deletion and modification Exute function . Except for addition, deletion and modification , Build table 、 You can also use this function to perform operations such as deleting tables .
The use method is similar to query .

// Add information 
insert = "insert into userdata.data (`id`,`name`,`Class`) values('0',' Zhang San ',' Class one ');";
// Delete 
del = "DELETE FROM userdata.data WHERE (`id` = '0');";
// modify 
update = "UPDATE userdata.data SET `name` = ' Li Si ' WHERE (`id` = '0');"

The corresponding operations can be realized by bringing these three statements in separately , modify x Bar information , If the modification is successful, an integer value is returned x.

mysqlDB mysql = new mysqlDB();
mysql.Exute(sql sentence , DBconn);