Question

I am developing a C# windows form application and on the main form I have a TabControl. It is declared in the Form1.Designer.cs file as follows:

public System.Windows.Forms.TabControl logFileCollectorTabControl;

In another class file in my project I want to use this TabControl as follows:

 logFileCollectorForm.logFileCollectorTabControl.TabPages.Add(newTabPage);

But I get the error ‘An object reference is required for the non-static field, method or property error’. So my question is, there must be an object of the Form class declared somewhere because the form launches when I launch the application, so how do I find out what that is, or how can I solve this issue, any help is greatly appreciated!

Answer 1

This is usually overcome by passing in an instance of Form1 to the constructor of the calling class, then keeping it in a field until needed.

//somewhere in Form1
OtherClass other = new OtherClass (this);

// OtherClass.cs
class OtherClass {
    Form1 _opener;

    public OtherClass(Form1 opener) {
        _opener = opener;
    }
}