js手动触发事件

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JS手动触发事件用到的方法:

1. createEvent(eventType)

参数:eventType 共5种类型:

Events :包括所有的事件. 
      HTMLEvents:包括 'abort', 'blur', 'change', 'error', 'focus', 'load', 'reset', 'resize', 'scroll', 'select', 
                                'submit', 'unload'. 事件
      UIEvents :包括 'DOMActivate', 'DOMFocusIn', 'DOMFocusOut', 'keydown', 'keypress', 'keyup'.
                              间接包含 MouseEvents. 
      MouseEvents:包括 'click', 'mousedown', 'mousemove', 'mouseout', 'mouseover', 'mouseup'. 
      MutationEvents:包括 'DOMAttrModified', 'DOMNodeInserted', 'DOMNodeRemoved', 
                                  'DOMCharacterDataModified', 'DOMNodeInsertedIntoDocument', 
                                  'DOMNodeRemovedFromDocument', 'DOMSubtreeModified'. 

2. 在createEvent后必须初始化

HTMLEvents和通用Events:
         initEvent(type, bubbles, cancelable); 分别表示事件名称,是否可以冒泡,是否阻止事件的默认操作。
UIEvents :
         initUIEvent( 'type', bubbles, cancelable, windowObject, detail )
MouseEvents: 
         initMouseEvent( 'type', bubbles, cancelable, windowObject, detail, screenX, screenY, 
                  clientX, clientY, ctrlKey, altKey, shiftKey, metaKey, button, relatedTarget )
MutationEvents :
         initMutationEvent( 'type', bubbles, cancelable, relatedNode, prevValue, newValue, 
                  attrName, attrChange ) 

3. 触发事件,dispatchEvent(event)

dom.dispatchEvent(eventObject), 参数eventObject表示事件对象,是createEvent()方法返回的创建的Event对象。

需要注意的是在IE 8以下版本请用fireEvent方法。

参考:https://www.cnblogs.com/jiangxiaobo/p/5830200.html

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