/*1.0*/
(function(){
    var doms = document.querySelectorAll('.limitText');
    var limitFn = function(){
        var el = this;
        var maxlength = el.getAttribute('data-maxlength');
        var showclass = el.getAttribute('data-limitfor');
        var showtag = null;
        if(el.value.length > maxlength){
            el.value = el.value.substr(0,parseInt(maxlength));
        }
        if(showclass && !/^\s*\s*$/.test(showclass)){//已定义且非(空或多个空格)
            showtag = document.querySelector(showclass);
        }
        showtag && (showtag.innerText = el.value.length + '/' + maxlength);
    };
    Array.prototype.forEach.call(doms,function(el,index){
        var maxlength = el.getAttribute('data-maxlength');
        if(maxlength != undefined && (maxlength = parseInt(maxlength)) ){
            el.addEventListener('compositionend', limitFn);
            el.addEventListener('blur', limitFn);
        }else{
            console.info('第 ' + (index + 1) + ' 个使用了"limitText"的元素没有定义data-maxlength');
        }
    });
})();