Home > Developer > Web Develop

JS AddEventListener RemoveEventListener

Source: Internet
Author: User
Developer on Alibaba Coud: Build your first app with APIs, SDKs, and tutorials on the Alibaba Cloud. Read more ＞

AddEventListener ,RemoveEventListener

    • AddEventListener () accepts three parameters.
      The first is the event type, such as click,keypress, the idea is not on , and it is all lowercase.
      The second is the handler function, which has an event parameter, and theevent includes the type, target, andso on.
      The third is the bool value, not the write is false, False is thebubbling event handler, andTrue is the capture event handler function.
    • RemoveEventListener() accepts three parameters.
      The first is the event type, ibid.
      The second is the processing function, must be registered with the same function, the anonymous function is useless. such as AddEventListener is fun1, RemoveEventListener also if fun1
      The third one ibid.
        var  father = document.getElementById ("Father"     var  fatherhandle = function   '---------Father-----------'  "Click", Fatherhandle, false  ); Father.removeeventlistener ( "Click", Fatherhandle, false ); //  valid  Father.removeeventlistener ("click", function  () {Console.log ('--no--')}, false ); //  invalid
    • multiple handlers for the same event type can be registered for the same object by calling AddEventListener multiple times, and called in the order in which they are registered.
      However, multiple registrations with the same parameters are not valid and will only be registered once.
    • Within the event handler, this is thenode object that points to the event target
    • The processing function return False is to block the default action,
      Preventdefault () of the event object in AddEventListenercancels the default action
    • Three stages of event propagation:
      Capture of events: internal objects that are triggered by the Window object
      Event handler: The third parameter is true for the capture function, andFalse for the bubbling handler function
      Event bubbling: Spreads from the innermost object to the root node outwards.
      The Stoppropagation () method that invokes the event object prevents the event from bubbling. If other functions are registered on the same object, they will continue to be called, but no more will be performed on the other objects.
      Stopimmediatepropagation () prevents other objects from propagating and also prevents other functions of the same object from executing.

varFather = document.getElementById ("Father"); varChild = document.getElementById ("Child"); varFatherhandle =function(event) {Console.log ('---------Father-----------')    }    varChildhandle =function(event) {Console.log ('---------child-----------')} father.addeventlistener ("Click", Fatherhandle,true); Child.addeventlistener ("Click", Childhandle,true); //Father-child
    false );    Child.addeventlistener (false);     // Child-father
var fatherhandle = function (event) {Console.log ('---------Father-----------')} var childhandle = function (event) {Console.log ('---------child-----------') Event.stoppropagation ()}

Father.addeventlistener ("Click", Fatherhandle, false);    Child.addeventlistener ("Click", Childhandle, false);    Child.addeventlistener ("click", Function (e) {console.log (' haha ')}, False); Child haha





























Call Order


 

     
 
       
  
         
   
      • To set an object property or HTML property to register a function first call
        •  
   
      • AddEventListener called in registered order
        •  
   
      • IE's attachevent () is not called sequentially, so the code should not be called since
        •  
  
       
 
     









<Body>    <H1ID= "Father">Father<spanID= "Child"onclick= "Fun ()">Child</span>    </H1><Script>    var Child=document.getElementById (" Child"); varChildhandle= function(event) {Console.log ('---------Child-----------')} child.addeventlistener ("Click", Childhandle,false); var Fun= function(e) {Console.log ('---------Property-----------')    }    //Property-child</Script></Body>




























JS AddEventListener RemoveEventListener



                

                    
This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or
reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or
complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

                

            


                            
Related Keywords:
                    

                                                    javascript addeventlistener error
                                                    uncaught typeerror cannot read property addeventlistener of undefined
                                                    node js sails js
                                                    implode js
                                                    js removechild
                                                    js strtoupper
                                                    dropzone js
                                            

                

                                                                    

        

            

                

                                        

                        

                    

                

                

    

                    
Contact Us

            
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
                products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
                content of the page makes you feel confusing, please write us an email, we will handle the problem
                within 5 days after receiving your email.

            

                If you find any instances of plagiarism from the community, please send an email to:
                info-contact@alibabacloud.com
                and provide relevant evidence. A staff member will contact you within 5 working days.
            

            



                

            

            
What's Trending

            
        

    


                                    

            

            
Top 10 Tags

                            datastax
                            versions
                            naming convention
                            zookeeper client
                            class definition
                            md5
                            microsoft sql server 2005
                            data structures
                            exception handling
                            error handling
                    

    


                    

            

            
Top 10 Keywords

                            microsoft download center down
                            wordpress address url site address url
                            wordpress address url
                            windows installer 4 0 download
                            302 not found
                            web address url definition
                            site address url wordpress
                            db2 integer
                            mac os installation step by step pdf
                            abbreviation for return
                    

    


                                

                    










  
      
  
            
                
                
            
  
      
  








                

            

        

    

    


    


  

    

      

        

          

            

              
A Free Trial That Lets You Build Big!

              
 Start building with 50+ products and up to 12 months usage for Elastic Compute Service 

              

                Get Started for Free
              

            

          

          

            

              
    
                
  • 
                  
    Sales Support
    
                  
    
                    1 on 1 presale consultation
                  
    
                  
    
                    Chat
                    Contact Sales
                  
    
                
    • 
                
  • 
                  
    After-Sales Support
    
                  
    
                    24/7 Technical Support
                    6 Free Tickets per Quarter
                    Faster Response
                  
    
                  
    
                    Open a Ticket
                  
    
                
    • 
                
  • 
                  
    
                  
     Alibaba Cloud offers highly flexible support services tailored to meet your exact needs. 
    
                  
    
                    Learn More
                  
    
                
    •