JavaScript的兼容

兼容总结

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• 如果两个都是属性，用逻辑 || 做兼容
• 如果有一个是方法，用三元做兼容
• 如果多个属性或方法，封装函数做兼容

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获取class属性值的兼容

function getClass (obj){
    if(obj.getAttribute("class") == null){
        return (obj.getAttribute("className")
    }else{
         return (obj.getAttribute("class")
    }
}

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获取className兼容

function byClassName (className){
    if(document.getElementsByClassName){
    	return document.getElementsByClassName(className);
	}else{
		var arr = [];
		var ele = document.getElementsByTanName("*");
		for(var i = 0; i < ele.length; i++){
			if(ele[i].className == className){
				arr.push(ele[i]);
			}
		}
		return arr;
	}
}

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滚动高度兼容

 var scrollTop = document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop;

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获取非行内样式的兼容

function getStyle(obj,attr){
    return obj.currentStyle ? obj.currentStyle[attr] : getConputedStyle(obj,1)[attr];
}

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获取事件Event兼容

oBtn.onclick = function(event){
	event = event || window.event;
}

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键盘值的兼容

function key(evt){
    var e = evt || window.event
    var keyvalue = e.getCode || e.charCOde || e.which;
    return keyvalue;
}

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阻止事件冒泡

function stop (e){
	var e = e || window.event;
	return e.stopPropagtion ? e.stopPropagtion() : e.cancelBubble = true;
}

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阻止超链接的默认行为

oA.onclick = function (e){
	var e = e || window.event;
	e.preventDefault ? e.preventDefault() : e.returnValue = false;
}

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事件源委托兼容

function target(evt){
    var e = evt || window.event;
    var target = e.target || e.srcElement;
    return target;
}

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获取鼠标值的兼容

function getButton(evt){
    var e = evt || window.event;
    if(evt){
        return e.button;
    }else if(window.event){
        switch(e.button){
            case 1 : return 0;
            case 4 : return 1;
            case 2 : return 2;
        }
    }
}

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添加事件的兼容

function addEventListener(obj,evt,fn,boo){
    if(obj.addEventListener){
        obj.addEventListener(evt,fn,boo);
    }else{
        obj.attachEvent("on" + evt , fn);
    }
}

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移除事件的兼容

function removeEventListener(obj,evt,fn,boo){
    if(obj.removeEventListener){
        obj.removeEventListener(evt,fn,boo);
    }else{
        obj.detachEvent("on" + evt , fn);
    }
}