Why program freezes when I add instance of Form in user control in C#? -

i new c# , using windows forms. have form1 button (button_save) , textbox . , have user control1 1 button (button1).

what trying in program is: when click on button1, text appear in textbox (in form1), enter new text , click save, button1 text change accordingly.

i explain when freeze happens:

there 2 parts:

first part: when created instance of user control1 in form1 participated in usercontrol1event , run program works fine , button1 text appears in textbox when click on it. second part when create instance of form1 in user control1 , participated in form1event , run program program freezes long time gives error pointing @ form1 instance in user control1 (as shown in screen shot).

anyone knows why happening ? doing wrong?

form1:

public partial class form1 : form {     public event eventhandler form1event;      usercontrol1 uc1 = new usercontrol1();      public form1()     {         initializecomponent();          controls.add(uc1);         uc1.visible = true;         uc1.usercontrol1event += new eventhandler(handleuc1);     }       string return_textbox_txt;     public string textbox_txt     {         { return return_textbox_txt; }      }        public void handleuc1(object sender, eventargs e) ////////////handle uc1  event      {         textbox1.text = uc1.buttontext;      }       private void button_save__click(object sender, eventargs e)//change button text     {         return_textbox_txt = textbox1.text;          form1event(this, e);     }   } 

user control1:

public partial class usercontrol1 : usercontrol {       string btntxt;        form1 frm1 = new form1();      public event eventhandler usercontrol1event;        public string buttontext      {         { return btntxt; }      }       private void usercontrol1_load(object sender, eventargs e)     {          frm1.form1event += new eventhandler(handleform1event);       }      public void handleform1event(object sender, eventargs e)      {          button1.text = frm1.textbox_txt;     }      private void button1_click(object sender, eventargs e)     {          btntxt = button1.text;          usercontrol1event(this, e);     } } 

it's expected behavior because of creating new form1 instance , on object constructing creates new usercontrol1 instance creates new form1 instance , on.

if need have owner of usercontrol1 inside instance can pass usercontrol1 constructor:

public partial class form1 : form {     ...     usercontrol1 uc1;     public form1()     {         initializecomponent();         // creates new control , pass owner via constructor parameter         uc1 = new usercontrol1(this);         controls.add(uc1);         uc1.visible = true;         uc1.usercontrol1event += new eventhandler(handleuc1);     }     ... }  public partial class usercontrol1 : usercontrol {     form1 frm1;     public usercontrol1(form1 owner)     {         // save user control owner passed constructor parameter local variable         frm1 = owner;     }     ... }