Create a edit page for ASP.Net Web App

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Create a new `razor` page to edit entries stored in a specific database table, ie Customers, Products and so on.

Inside the Model (ie .cs file) create a variable to store each field:

int ID = -1;
string Name="";
string Email="";
string Address="";
string TelNo="";

Now in the `OnGet` method create a MySQL database connection:

public void OnGet()
{
    using var connection = GetConnection; // this gets the connection

    connection.Open(); // you must open the connection
            
    connection.Close();
}

Now between the `connection.Open()` and the `connection.Close()` create the command and SQL to retrieve the record you want to edit:

using var Command = new MySqlCommand("SELECT * FROM Customer where ID=@id", connection);
Command.Parameters.AddWithValue("@id", id);
using var reader = Command.ExecuteReader();

Now, after you have created the reader and executed it we need to check if it has selected anything:

if(reader.HasRows)
{
    while(reader.Read())
    {
        ID = reader.GetInt32(0);
        Name = reader.GetString(1);
        Email = reader.GetString(2);
        Address = reader.GetString(3);
        TelNo = reader.GetString(4);
    }
}

We assign values to the variables we created above. Remember your database table is likely to be different and your variables should match your table and the numbers in the `reader.Get` lines should be the order of the fields in the table.

Now in the `html` page, you need to set up your form.