从单独的设计时表单访问设计时控件

Question

I am looking for the easiest way to access the design-time controls created in the main form of a windows application form from another form. I am going to want to manipulate all the controls and would prefer not to make getter and setter methods. There will only ever be a couple of additional forms that are only used for input in order to change the states of controls on the primary form--so I am not concerned about best practices here because this is not going to be a big project where many people are going to be working and multiple variables are going to get confused, and because I am completely new to this and want something that works. I am not working in a professional programming environment.

I would like to be able to simply address them with dot syntax somehow.

That said: Merely changing the type to "public" doesn't seem to allow me to do this however.

So, for a textbox, when I change it from:

private System.Windows.Forms.RichTextBox AssignmentSectNumber;

To

public System.Windows.Forms.RichTextBox AssignmentSectNumber;

Where the C# system automatically declares it once I put it into my form, I still can not access it from form two with

Form1.AssignmentSectNumber.Text

Is there any way that I can set up the controls in Form1 so that they can be addressed in Form2 either by going through Form1 through dot syntax or simply by directly addressing them?

PS: I do not see a way to make controls "public" under any of the properties listed when I put them into a form at design time. Am I missing something?

Answer 1

I do not see a way to make controls "public" under any of the properties listed when I put them into a form at design time. Am I missing something?

Select the Control and then in the Properties Pane, change its Modifiers Property to Public.

When I run the program form1 appears on the screen. Doesn't this mean that there must be an instance of it? If the name of that intance isn't form1 what would it be?

You need to access the currently running instance of Form1. There are many ways to do this. One very simple method is to set the Owner of the secondary form when you call its Show() method:

// ... from within Form1 ...
Form2 f2 = new Form2();
f2.Show(this); // <-- setting Form1 as the "owner" of Form2 via "this"

Now, over in Form2, you cast the .Owner property back to Form1 and access the Control(s) you changed the Modifiers Property for to Public:

// ... over in Form2 ...
Form1 f1 = (Form1)this.Owner;
f1.label1.Text = "Hello from Form2!";