将两个Javascript函数组合到一个窗口中.nload不起作用

这就是我最终所做的，现在所有的函数都工作了。

var ul;
var li_items;
var imageNumber;
var imageWidth;
var prev, next;
var currentPostion = 0;
var currentImage = 0;

function init() {
    ul = document.getElementById('image_slider');
    li_items = ul.children;
    imageNumber = li_items.length;
    imageWidth = li_items[0].children[0].clientWidth;
    ul.style.width = parseInt(imageWidth * imageNumber) + 'px';
    prev = document.getElementById("prev");
    next = document.getElementById("next");
        prev.onclick = function() {
        onClickPrev();
    };
    next.onclick = function() {
        onClickNext();
    };
}
function animate(opts) {
    var start = (new Date());
    var id = setInterval(function() {
        var timePassed = (new Date()) - start;
        var progress = timePassed / opts.duration;
        if (progress > 1) {
            progress = 1;
        }
        var delta = opts.delta(progress);
        opts.step(delta);
        if (progress == 1) {
            clearInterval(id);
            opts.callback();
        }
    }, opts.delay || 17);
    //return id;
}
function slideTo(imageToGo) {
    var direction;
    var numOfImageToGo = Math.abs(imageToGo - currentImage);
    // slide toward left
    direction = currentImage > imageToGo ? 1 : -1;
    currentPostion = -1 * currentImage * imageWidth;
    var opts = {
        duration: 1000,
        delta: function(p) {
            return p;
        },
        step: function(delta) {
            ul.style.left = parseInt(currentPostion + direction * delta * imageWidth * numOfImageToGo) + 'px';
        },
        callback: function() {
            currentImage = imageToGo;
        }
    };
    animate(opts);
}
function onClickPrev() {
    if (currentImage === 0) {
        slideTo(imageNumber - 1);
    } else {
        slideTo(currentImage - 1);
    }
}
function onClickNext() {
    if (currentImage == imageNumber - 1) {
        slideTo(0);
    } else {
        slideTo(currentImage + 1);
    }
}
window.onload = init;

function addLoadEvent(func) {
    var oldonload = window.onload;
    if (typeof window.onload != 'function') {
        window.onload = func;
    } else {
        window.onload = function() {
            if (oldonload) {
                oldonload();
            }
            func();
        }
    }
}
function fun2() {
    // Google spreadsheet js
    google.load('visualization', '1', {
        callback: function() {
            var query = new google.visualization.Query('https://docs.google.com/spreadsheets/d/1sA7M5kG6Xo8YScD1Df38PIA_G0bvhGRdqoExXg0KJTs/gviz/tq?tqx=out:html&tq?gid=0&headers=0&range=A1:C');
            query.send(displayData);
        }
    });
    function displayData(response) {
        numRows = response.getDataTable().getValue(0, 0);
        document.getElementById('data').innerHTML = numRows;
    }

}
addLoadEvent(fun2);
addLoadEvent(function() {
});

我不久前发现了这个函数，信不信由你，我仍然需要经常使用它addEventLoad()只需在传递要加载的函数时调用addEventLoad。

其工作方式相对简单：如果window.onload尚未被分配函数，则传递给addLoadEvent的函数将被简单地分配给window.onlead。如果已经设置了window.onlad，则会创建一个全新的函数，该函数首先调用原始的onload处理程序，然后再调用新的处理程序。

此代码段将在window.onload 上加载3个函数

代码段

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}
function alert1() {
  alert("First Function Loaded");
}
function alert2() {
  alert("Second Function Loaded");
}
function alert3(str) {
  alert("Third Function Loaded; Msg: " + str);
}
addLoadEvent(alert1);
addLoadEvent(alert2);
addLoadEvent(function() {
  alert3("This works");
});

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