問題描述

最近在使用jquery模擬a標簽的click事件，無法觸發(fā)其默認行為。即click()或trigger('click')無法觸發(fā)href跳轉。

<a id="aBtn" );//同樣無法跳轉，不生效

下面就來一起分析下其原因與解決方法吧

問題原因

jquery內(nèi)部實現(xiàn)click或trigger方法時，并未真正模擬用戶點擊事件，只是模擬了事件對象及冒泡的觸發(fā)。（最后附有jquery實現(xiàn)源碼供參考）

解決方案

解決思路：在原生dom觸發(fā)click事件或利用事件冒泡來解決。

原生dom觸發(fā)click

<a id="aBtn" ).click();//原生dom觸發(fā) 或者$('#aBtn')[0].click();//jquery對象轉為dom對象再觸發(fā)

利用子元素事件冒泡

<a id="aBtn" > <span id="spanBtn">去卡咪官網(wǎng)</span></a>$('#spanBtn').click();//或者$('#spanBtn').trigger('click');

jquery trigger()實現(xiàn)源碼(8159行-8304行)

源碼鏈接地址

關鍵摘要：

// Fire handlers on the event path （8237行）i = 0;while ( ( cur = eventPath[ i++ ] ) && !event.isPropagationStopped() ) {	lastElement = cur;	event.type = i > 1 ?		bubbleType :		special.bindType || type;	// jQuery handler	handle = ( dataPriv.get( cur, "events" ) || {} )[ event.type ] &&		dataPriv.get( cur, "handle" );	if ( handle ) {	//******自身trigger('click')或click()時,會調(diào)用緩存列表里的事件回調(diào)函數(shù),但未執(zhí)行elem.click()******		handle.apply( cur, data );	}	// Native handler	handle = ontype && cur[ ontype ];	if ( handle && handle.apply && acceptData( cur ) ) {		event.result = handle.apply( cur, data );		if ( event.result === false ) {			event.preventDefault();		}	}}

// If nobody prevented the default action, do it now （8263行）if ( !onlyHandlers && !event.isDefaultPrevented() ) {	if ( ( !special._default ||		special._default.apply( eventPath.pop(), data ) === false ) &&		acceptData( elem ) ) {		// Call a native DOM method on the target with the same name as the event.		// Don't do default actions on window, that's where global variables be (#6170)		if ( ontype && isFunction( elem[ type ] ) && !isWindow( elem ) ) {			// Don't re-trigger an onFOO event when we call its FOO() method			tmp = elem[ ontype ];			if ( tmp ) {				elem[ ontype ] = null;			}			// Prevent re-triggering of the same event, since we already bubbled it above			jQuery.event.triggered = type;			if ( event.isPropagationStopped() ) {				lastElement.addEventListener( type, stopPropagationCallback );			}   //******子元素trigger('click')或click()，會執(zhí)行elem.click()******			elem[ type ]();			if ( event.isPropagationStopped() ) {				lastElement.removeEventListener( type, stopPropagationCallback );			}			jQuery.event.triggered = undefined;			if ( tmp ) {				elem[ ontype ] = tmp;			}		}	}}