c# - Can't edit Form1 textbox from Form2 -

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• how update textbox in form1 form2? 3 answers

in form1 have textbox filled char array values (*). in form2 change 1 of array values (change * letter) , have update form1 textbox. when press button - nothing happens. form2 code snippet:

 private void button2_click(object sender, eventargs e)         {             ....              ....              letter = (char)form1.number;               textbox1.text = letter.tostring(); //shows me letter i'm replacing '*'         }   private void button3_click(object sender, eventargs e)         {             frm1 = new form1();              form1.chararray[convert.toint32(frm1.numericupdown2.value)] = letter; //which array value i'm changing              frm1.textbox2.text = string.empty;              (int = 0; < frm1.numericupdown1.value; i++)             {                 frm1.textbox2.text += form1.chararray[i];             }         } 

instead of editing form1-window talking about, creating new (yet invisible) 1 in event-handler , perform operations on that.

solution:

as doing fields (chararray, number), have give method "access" instance of form1 exists!

option 1: have done chararray , number, add static field form1 (something public static form1 instance;), , assign correct instance. example, put form1.instance = this; inside of form1's constructor.

option 2: wherever creating , showing form2-window (i guess there new form2().show() in code , bet has access instance of form1 - maybe within form1), pass right instance of form1 constructor argument, i.e. change form2's constructor accepts parameter of type form1 , call new form2(therightinstanceofform1).

summary: although "option 2" cleaner one, guess give more trouble "option 1": not did define several static fields (so not make difference add one), if using visual studio designer design form2, break change constructor...