C # The use of events in Form 2 triggers Form 1 so that form 1 executes a method

Step 1: in Form 2

Define Delegation

Define events

 
Public Delegate VoidChange (StringNewsendemails );//The definition of Delegate and delegate should be the same as the actual method in the UIPublic EventChange mychangeevent;//Define events
 

In a method or event

Execution event

 
Mychangeevent (sb. tostring ());//Execution event
 

Step 2: in Form 1

Define a method (event execution method) that corresponds to the form parameter and return value of Form 2 Delegate)

//Event execution MethodPublic VoidSetsendemail (StringNewemails ){This. Textboxsendemaillist. Text =Newemails ;}
 

Register events in Load

Private VoidButtonsendemailsum_click (ObjectSender, eventargs e) {formsendemailsift fromsendemailsift=NewFormsendemailsift (This. Qqentitylist); fromsendemailsift. mychangeevent+ =NewFormsendemailsift. Change (setsendemail );//Register an eventFromsendemailsift. Show ();}
 

In this way, you can click a button in Form 2 or execute a method in Form 1 to execute the method you want.CodeNow

To directly pass values in different forms