如何使用存储过程从 ASP.NET 记录计数？

Question

Can you help me? I am trying to output the number of depositors which has the total of 5 but when I run the program it outputs only 1. I used stored procedure for this matter. I think something is missing when in the codes below and I don't know. I tried my best to search in the internet.

This code is in C#

protected void Page_Load(object sender, EventArgs e) {

        if (!IsPostBack)
        {
            CountAllUsers();
      
        }

      

    }


protected void CountAllUsers()
    {
        using (MySqlConnection mycon = new MySqlConnection(constring))
        {
            
            mycon.Open();
            MySqlCommand cmd = new MySqlCommand("countallusers", mycon);
            cmd.CommandType = CommandType.StoredProcedure;
            MySqlDataAdapter adx = new MySqlDataAdapter(cmd);
            DataSet ds= new DataSet();
            adx.Fill(ds);

            mycon.Close();

            lblDepositors.Text = ds.Tables[0].Rows.Count.ToString();
        }

Answer 1

You can use ExecuteScalar to do the query for counting the number of records. Replace TABLE_NAME with your table.

FYI, you don't have to call mycon.Close(); , as you apply using statement, when it ends, it will dispose the connection automatically.

Updated : Added using block for MySqlCommand for Disposable best practice as suggested by @Dai.

protected void CountAllUsers()
{
    using (MySqlConnection mycon = new MySqlConnection(constring))
    {  
        using (MySqlCommand cmd = new MySqlCommand("SELECT COUNT(*) FROM TABLE_NAME", mycon)) 
        {
            cmd.CommandType = CommandType.Text;
            mycon.Open();

            var count = Convert.ToInt32(cmd.ExecuteScalar());
            lblDepositors.Text = count.ToString();
        }       
    }
}

MySqlCommand.ExecuteScalar Method

ExecuteScalar method to retrieve a single value (for example, an aggregate value) from a database.

Answer 2

I already solved. Thanks!

protected void CountAllUsers()
    {
        using (MySqlConnection mycon = new MySqlConnection(constring))
        {
            
            mycon.Open();
            MySqlCommand cmd = new MySqlCommand("SELECT COUNT(id) as count from depositors_tbl", mycon);
            MySqlDataAdapter ada = new MySqlDataAdapter();
            DataSet dt = new DataSet();
            ada.SelectCommand = cmd;
            ada.Fill(dt);
            mycon.Close();

            lblDepositors.Text = dt.Tables[0].Rows[0]["count"].ToString();
        }

    }