摘要：放大鏡頁面加載完畢后執行親沒有數據哦動態添加標簽加載地址后傳入輸出一個函數在上面則定義好這個函數接受一個就是資源類型循環輸出可先查看數據點擊一次，從多少開始獲取獲取指定區間范圍隨機數，包括和如獲

        //頁面加載完畢后執行
        window.onload = function () {

            var oDemo = document.getElementById("demo");
            var oMark = document.getElementById("mark");
            var FloatBox = document.getElementById("float-box");
            var SmallBox = document.getElementById("small-box");
            var bigBox = document.getElementById("big-box");
            var bigImg = bigBox.getElementsByTagName("img")[0];

            oMark.onmouseover = function (){
                FloatBox.style.display = "block";
                bigBox.style.display = "block";
            }

            oMark.onmouseout = function (){
                FloatBox.style.display = "none";
                bigBox.style.display = "none";
            }

            oMark.onmousemove = function (ev){

                var ev = ev || window.event;
                var left = ev.clientX - oDemo.offsetLeft - SmallBox.offsetLeft - FloatBox.offsetWidth / 2;
                var top = ev.clientY - oDemo.offsetTop - SmallBox.offsetTop - FloatBox.offsetHeight / 2;

                if(left < 10){

                    left = 0;

                }else if(left >= oMark.offsetWidth - FloatBox.offsetWidth - 10){

                    left = oMark.offsetWidth - FloatBox.offsetWidth;

                }

                if(top < 10){

                    top = 0;

                }else if(top >= oMark.offsetHeight - FloatBox.offsetHeight - 10){

                    top = oMark.offsetHeight - FloatBox.offsetHeight;

                }

                FloatBox.style.left = left + "px";
                FloatBox.style.top = top + "px";

                var scaleX = left / (oMark.offsetWidth - FloatBox.offsetWidth);
                var scaleY = top / (oMark.offsetHeight - FloatBox.offsetHeight);

                bigImg.style.left = -scaleX * (bigImg.offsetWidth - bigBox.offsetWidth) + "px";
                bigImg.style.top = -scaleY * (bigImg.offsetHeight - bigBox.offsetHeight) + "px";

            }

        }
        

        function fn1(data){
            var html = "";
            var oUl = document.getElementsByTagName("ul")[0];

            console.log(data);

            if(data.total != -1){
                for(var i=0; i "+ data.books[i].author_intro +"
"+ data.books[i].summary +"
 
" + data.books[i].publisher + "
";
    
                }
    
                oUl.innerHTML = html;
            
            }else{
                document.body.innerHTML+="
親~~ 沒有數據哦~~~
";
            }
            
        }
    
    window.onload = function (){
        
        var oBtn = document.getElementById("btn");
        var iNow = 0;
        oBtn.onclick = function (){
            //動態添加 script 標簽   加載URL地址 后傳入 callback=fn1 輸出一個函數, 在上面則定義好這個函數, 接受一個data 就是資源  json類型,循環輸出, 可先console.log(dara) 查看數據
            var oScript = document.createElement("script");
            
            oScript.src="https://api.douban.com/v2/book/search?q=%E6%A0%A1%E5%9B%AD&count=10&start="+ iNow +"&callback=fn1";
            document.head.appendChild(oScript);
            
            // 點擊一次+10，從多少開始獲取
            iNow += 10;
        
        }
            
    }

function randomFrom(lowerValue,upperValue)
{
    return Math.floor(Math.random() * (upperValue - lowerValue + 1) + lowerValue);
}
//如獲取1-100之間的隨機數
console.log(randomFrom(1,100));

1、快速排序
    
    /** 
     *   得到中間那位那位數,然后循環判斷, arr[i] < 中間數 則push leftArr, 否則push rightArr, 最后返回 left數組 "拼接" 中間數 + right數組 
     */
    function sort(arr){
    
        if(arr.length <= 1){
            return arr;
        }
    
        var numIndex = Math.floor(arr.length/2);
        var numVal = arr.splice(numIndex,1);
        var leftArr = [];
        var rightArr = [];
    
        for(var i=0; i
5、數組去重
1、indexOf 去重

/**
 *   當arr的第一次出現的位置 == i  則是第一次出現就push到tempArr
 */
function unique(arr){

    if (arr.length <= 1){
        return arr;
    }

    var tempArr = [];

    for(var i=0; i
6、深度拷貝
/** 
 *     深度拷貝
 *     使用for in 在循環賦值，避免對象引用
 */
function copy(obj){

    if(typeof obj != "object"){
        return obj;
    }

    var newObj = {};

    for(var attr in obj){

        newObj[attr] = copy(obj[attr]);

    }

    return newObj;

}