js 事件相关

Posted 2021-01-05 justSmile2

1.绑定

function(element, type, handler){
        if (element.addEventListener) {
            element.addEventListener(type, handler, false);
        }
        else 
            if (element.attachEvent) {
                element.attachEvent("on" + type, handler);
            }
            else {
                element["on" + type] = handler;
            }
    }

2.删除

function(element, type, handler){
        if (element.removeEventListener) {
            element.removeEventListener(type, handler, false);
        }
        else 
            if (element.detachEvent) {
                element.detachEvent("on" + type, handler);
            }
            else {
                element["on" + type] = null;
            }
    }

3.阻止默认事件

function(event){
        if (event.preventDefault) {
            event.preventDefault();
        }
        else {
            event.returnValue = false;
        }
    }

4.不传播事件（阻止冒泡）

function(event){
        if (event.stopPropagation) {
            event.stopPropagation();
        }
        else {
            event.cancelBubble = true;
        }
    }

5.获得event的target

function(event){
        return event.target || event.srcElement;
    }