摇曳的蔷薇
直接在窗口上触发的事件窗口没有“捕获阶段” ”。如果您查看事件调度和 DOM 事件流图形，您可以看到该流程开始于 窗口，因此此类事件将已处于“目标阶段”状态。从第一步开始。这意味着对于此类事件，capture 标志是无用的，因为所有事件侦听器都将在“目标阶段”，因为它们会在您的捕获处理程序之前触发。您无法停止将事件传播到先前设置的处理程序”无论如何，所以const phases_dict = { [Event.CAPTURING_PHASE]: 'Capturing Phase', [Event.AT_TARGET]: 'Target Phase', [Event.BUBBLING_PHASE]: 'Bubbling Phase'};// First listener defined without capturing flag, will fire first anywaywindow.addEventListener( 'blur', evt => { const current_phase = phases_dict[ evt.eventPhase ]; console.log( 'bubble blur is in', current_phase );}, { capture: false } ); // fire at bubbling phase// Second listener with capturing flagwindow.addEventListener( 'blur', evt => { // This one will also capture the events on Elements in the Document // For our case, we only want the one on Window if( evt.currentTarget === evt.target ) { const current_phase = phases_dict[ evt.eventPhase ]; console.log( 'capture blur is in', current_phase ); }}, { capture: true } ); // fire at capturing phase// To show that bubbling events work as intended// We also register click eventswindow.addEventListener( 'click', evt => { const current_phase = phases_dict[ evt.eventPhase ]; console.log( 'bubble click is in', current_phase );}, { capture: false } ); // fire at bubbling phasewindow.addEventListener( 'click', evt => { const current_phase = phases_dict[ evt.eventPhase ]; console.log( 'capture click is in', current_phase );}, { capture: true } ); // fire at capturing phase<pre>Click anywhere in this frame then click somewhere else in SO's page to trigger focus event</pre>请注意，您可以停止 Elements 的传播。 模糊事件，但不模糊Window事件。您必须找到其他方法来阻止当前的侦听器，也许是使用标志变量？