js常用函数的封装

function chechOutType(obj){
    var o = Object.prototype.toString.apply(obj);
    switch(o){
        case '[object Function]':
            o = 'isfunction';
            break;
        case '[object Object]':
            o = 'isObject';
            break;
        case '[object RegExp]':
            o = 'isRegExp';
            break;
        case '[object Array]':
            o = 'isArray';
            break;
        //这个未检测
        case '[object JSON]':
            o = 'isJSON';
            break;
        case '[object String]':
            o = 'isString';    
            break;    
        case '[object Number]':
            o = 'isNumber';    
            break;    
        case '[object Boolean]':
            o = 'isBoolean';
            break;
        //这个不常用，webgl会涉及
                case '[object ArrayBuffer]':
                   o = 'isArrayBuffer'
                  break;
        default:
            alert("not of them");
    }
    return o;
};

//另一种写法
 var type = function(o){
     var s = Object.prototype.toString.apply(o);
     return s.match(/\[object (.*?)\]/)[1].toLowerCase();
 }

 var array=['Null','Undefined','Object','Array','String','Number','Boolean','Function','RegExp','NaN','Infinite'];
 array.forEach(function(t){
     type["is"+t] = function(o){
     return type(o) === t.toLowerCase();
 }

 });
 var a=54;
 console.log(type.isArray(a));
`
</pre>
//添加事件监听
<pre>`
function addEventHandler(target,type,func){
  if(target.addEventListener){
    target.addEventListener(type, func, false);
  }else if(target.attachEvent){
    target.attachEvent("on" + type, func);
  }else{
    target["on" + type] = func;
  }  
}
`</pre>
//得到style
<pre>`
   function getstyle(obj,name){
     if(obj.currentStyle){
         return obj.currentStyle[name];
       }else{
         return getComputedStyle(obj,false)[name];
       }
   }
`</pre>
//自己常用
<pre>`
function con(obj,type){
        type = type||'l';
    switch(type){
        case 'l':
            console.log(obj);
            break;
        case 'i':
            console.info(obj);
            break;
        case 'e':
            console.error(obj);
            break;
        case 'd':
            console.debug(obj);
            break;
        case 'w':
            console.warn(obj);
            break;
        case 'dir':
            console.dir(obj);
            break;
        case 'assert':
            console.assert(obj);
            break;
        case 'trace':
            console.trace(obj);
            break;
    }
}
`</pre>
//通过类名查找元素，但是要给定一个父元素
<pre>`
function getElementsByClass(oParent, target) {
    var aEle = oParent.getElementsByTagName('*');
    var aResult = [];
    var reg = new RegExp('\\b' + target + '\\b', 'i');
    console.info(reg);
    var i = 0;
    for(i = 0; i &lt; aEle.length; i++) {
         if(reg.test(aEle[i].className)) {

             aResult.push(aEle[i]);
         }
    }
    return aResult;
}

function myQuery(obj){
    //保存符合条件的子元素
    this.children=[];
    switch(typeof obj){
        case 'function':
            //函数
            addEventHandler(window,'load',obj);
            break;
        case 'string':
            var objWithoutInitial = obj.substring(1);
            switch(obj.charAt(0)){
                case '#':
                //id选择器
                    var o = document.getElementById(objWithoutInitial);
                    this.children.push(o);
                    break;
                case '.':
                //类选择器
                    this.children = getElementsByClass(document,objWithoutInitial);
                    break;
                default:
                //tag元素选择器
                    this.children =document.getElementsByTagName(obj);                
            }
            break;
        case 'object':
            this.children.push(obj);
            break;
        default:
            alert('不支持此用法');
    }
}
function $(obj){
    return new myQuery(obj);
}

//实现数组换行显示，,默认每十行一换行，未实现等距输出
function showArray(arr,len){
    len = len|10;
    var showArr = arr;
    for(var i=0;i<(arr.length/len);i++){
        showArr = arr.slice(0+len*i,len+len*i);
        console.log(showArr);
    }
}