How to change default value of combo box

Question

I am trying to make SQL statement based on item selected throw combo box. I want to have default item selected as ID, but now it returns NULL. What am I doing wrong?

private void Win_Shown(object sender, EventArgs e)
{
   myBox.SelectedValue = "ID";
   myBox.SelectedText = "ID";
   myBox.SelectedItem = "ID";

   myBox.Items.Add("ID");
   myBox.Items.Add("Name");
   myBox.Items.Add("Surname");
   myBox.Items.Add("Mobile"); 
}

Then in for SQL statement

MySQL.DisplayAndSearch("SELECT * FROM Data WHERE " + this.myBox.SelectedItem.ToString() + " LIKE '%" + txt_Search.Text + "%'", dataGridView1);

Thank for any help :)

Answer 1

You are selecting the item before inserting:

private void Win_Shown(object sender, EventArgs e)
{
   // first, add the items   
   myBox.Items.Add("ID");
   myBox.Items.Add("Name");
   myBox.Items.Add("Surname");
   myBox.Items.Add("Mobile"); 

   // now select it
   myBox.SelectedItem = "ID";
}