Try this,
Passing string from comBox to textBox
Code Snippet
textBox1.Text = comboBox1.SelectedItem.ToString();
If you want to convert String to Number, try to convert them in safe way:
Code Snippet
int
Num;
if (int.TryParse(comboBox1.SelectedItem.ToString(), out Num))
{
textBox1.Text = Num;
}
else
{
MessageBox.Show("Sorry! String wasn't Convertable.");
}
Hope this helps.