C#: Convert a string to an object reference.

Question

Basically a button's tag property is the name of an existing combobox which I need to dynamically reference. It's a generic function to handle multiple buttons. Help

private void SQLButton(object sender, EventArgs e)
{
    magic(((Button)sender).Tag.ToString());
}

private void magic(string currentcombo)
{
    string CurrentText = (ComboBox).(currentcombo).Text;
}

Answer 1

If you have the string id value of a control then you can use FindControl to get a reference to the control.

Something like ...

Button btn = (Button)FindControl("some_id");

Answer 2

I think I understand what you're after -

You'll want to change your "magic" routine to something like:

private void magic(string currentCombo) {
    ComboBox box = this.Controls.Find(currentCombo) as ComboBox;
    if(box != null) {
        // You can do your "work" here...
        string currentText = box.Text;
    }
}

Answer 3

You can set the Tag property to the actual ComboBox and avoid your problem altogether.

//code when defining your button...
{
     sqlButton.Tag = comboBoxA;  //instead of comboBoxA.Name
}

private void SQLButton(object sender, EventArgs e)
{
    Button button = sender as Button;
    ComboBox comboBox = button.Tag as ComboBox;

    if (comboBox == null ) 
    {...}
    else
    {
        magic(comboBox);
    }
}

private void magic(ComboBox currentcombo)
{
    string CurrentText = currentcombo.Text;
}

Answer 4

I don't know if its winforms or asp.net. I am assuming it to be winforms

You could use this.Controls(theNameofTheControl) instead of magic.

Answer 5

Have a look at the Controls.Find Method, to get the instance of the Control using the name.

Answer 6

If currentcombo paramter in magic function is the identifier for the control you are going to change then use Page's function FindControl:

string CurrentText = ((ComboBox)FindControl(currentcombo)).Text;

Page.FindControl() method searches the page naming container for a server control with the specified identifier.

Answer 7

I love the way you can reassign, so to speak. I have 7 buttons and now, thanks to you, I only have 5 Events instead of 35 separate events. Really allowed me to modularize and centralize events. BTW, did this with the 7 ListViews, but sorta different and ContextMenu items. Thanks again. Really appreciate that tip.