how to reference a non static object in a static method

Question

I've created a textbox and want to reference it in a static methd. how can I do that? here;s my code

    private void Form1_Load(object sender, EventArgs e)
    {
        TextBox textbox2 = new TextBox();
        textbox2.Text = "A";
    }

    static void gettext() 
    {
        textbox2.Text = "B"; //here is my problem
    }

Also notice that in your code textbox2 in Form1_Load is local to the method, not to the class. Define Textbox textbox2 outside Form1_Load — rene, Mar 11 '13 at 10:36
http://stackoverflow.com/questions/498400/an-object-reference-is-required-for-the-nonstatic-field-method-or-property-wi — Gopesh Sharma, Mar 11 '13 at 10:36
can anybody tell me how can I make an object reference to texbox2 in my static method? — user1853846, Mar 11 '13 at 10:42
Your [other question](http://stackoverflow.com/q/15316651/1174942) is about the same thing and is answered perfectly. Please read it carefully. You need to study about `static` and instances. — Mohammad Dehghan, Mar 11 '13 at 10:54

score 6 · Answer 1 · answered Mar 11 '13 at 10:35

6

You would need to pass it into the static method somehow, easiest option is to just expand the method signature to accept the textbox:

static void gettext(TextBox textBox) 
{
    textBox.Text = "B"; //here is my problem
}

answered Mar 11 '13 at 10:35

Lloyd

29,197
4
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@user1853846 Don't forget to accept the answer you feel is the best (in this case, Lloyd's) – Nolonar Mar 11 '13 at 10:58

score 4 · Answer 2 · answered Mar 11 '13 at 10:35

4

You should give your textbox as a parameter to the static method

static void gettext(TextBox textbox)
{
    textbox.Text = "B";
}

answered Mar 11 '13 at 10:35

Nolonar

5,962
3
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score 2 · Answer 3 · answered Mar 11 '13 at 10:35

I'm not sure you understand what static means, static means that it belongs to the CLASS not an INSTANCE of the class. Possibly a better solution to your problem would be to create an instance method which set the text.

// private variable
private TextBox textbox2;

private void Form1_Load(object sender, EventArgs e)
{
    // refers to private instance variable
    textbox2 = new TextBox();
    textbox2.Text = "A";
}

private void gettext() 
{
    // refers to private instance variable
    textbox2.Text = "B";
}

If you're having difficulty understanding static, odds are you don't need to use it. Static members are available to all instances of a class but don't belong to any of them, which means static methods cannot access private members.

Why did this get downvoted? It doesn't make use of `static` methods, but as far as I can see, this is a totally valid answer, am I missing something? — Nolonar, Mar 11 '13 at 10:47
also not sure why (it is not directly answering the explicit question, yes, but it certainly gives what is likely the best and most useful answer, in my mind) +1 — Kevin Versfeld, Mar 11 '13 at 10:52

score 2 · Answer 4 · answered Mar 11 '13 at 10:37

2

You can do so

static void gettext(TextBox textbox2) 
{
    textbox2.Text = "B";
}

And in code

private void Form1_Load(object sender, EventArgs e)
{
    YourClass.gettext(textbox2);
}

answered Mar 11 '13 at 10:37

Alex

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3
42
58

score -1 · Answer 5 · answered Mar 11 '13 at 10:45

-1

You can create a static variable set on Load :

private static readonly TextBox _textBox = new TextBox();

private void Form1_Load(object sender, EventArgs e)
{
    _textBox.Text = "A";
}

static void gettext()  
{ 
    _textbox2.Text = "B";
}

answered Mar 11 '13 at 10:45

Toto

7,491
18
50
72

The textBox is readonly and never reassigned, only the Text property. If you prefer, you remove the readonly and create the TextBox on the Load method. – Toto Mar 11 '13 at 13:08

how to reference a non static object in a static method

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