events - Javascript Focus and Blur -

every thing works fine except 'blur', reason feedback when no characters inputed, input username that's less 5 checkusername function that's attached 'blur' not send feedback(also have no error messages within developer tool).

function checkusername(){     var username=el.value;     if(username<5){         elmsg.classname='warning';         elmsg.textcontent='not  long enough...';     }else{         elmsg.textcontent='';     } }  function tipusername(){     elmsg.classname='tip';     elmsg.innerhtml='username must @ least 5 characters'; }  var el=document.getelementbyid('username'); var elmsg=document.getelementbyid('feedback');  el.addeventlistener('focus',tipusername,false); el.addeventlistener('blur',checkusername,false); 

to check length of string, use "somestring".length:

/* ... */ if(username.length < 5){ /* ... */ 

demo

function checkusername(){      var username=el.value;      if(username.length < 5){          elmsg.classname='warning';          elmsg.textcontent='not  long enough...';      }else{          elmsg.textcontent='';      }  }    function tipusername(){      elmsg.classname='tip';      elmsg.innerhtml='username must @ least 5 characters';  }    var el=document.getelementbyid('username');  var elmsg=document.getelementbyid('feedback');    el.addeventlistener('focus',tipusername,false);  el.addeventlistener('blur',checkusername,false);

<input type="text" id="username" placeholder="enter username..." />  <div id="feedback"></div>