用js显示点点点

function wordlimit(cname,wordlength){
  var cname=document.getElementsByClassName(cname);
  for(var i=0;i<cname.length;i++){
  var nowhtml=cname[i].innerHTML;
  var nowlength=cname[i].innerHTML.length;
  if(nowlength>wordlength){
  cname[i].innerHTML=nowhtml.substr(0,wordlength) + '…';
  }
  }
  }
  wordlimit("description",20);