var set = new Set(); var fileArr=""; var depCode=$('#depCode').attr("data-value");//取值 if(depCode!=''&&depCode!=undefined){ var array=depCode.split(","); for(var i=0;i<array.length;i++){ set.add(array[i].substr(0,3)) } set.forEach(function (element, sameElement, set) { fileArr+=element+","; }); } if(fileArr.indexOf(value.substr(0,3))>-1){ return false; }