Home > PCB_Event > isEventListenerAlreadyExist
PCB_Event.isEventListenerAlreadyExist() method
Query whether the event listener exists
Signature
typescript
public isEventListenerAlreadyExist(id: string): boolean;1
Parameters
Parameter | Type | Description |
|---|---|---|
id | string | Event ID |
Returns
boolean
Whether the event listener exists
Example
javascript
const listenerId = '嘉立创示例_event_exist';
// 1. 注册前查询:应为 false
const before = eda.pcb_Event.isEventListenerAlreadyExist(listenerId);
console.log('before:', before);
// 2. 注册一个鼠标事件监听使 id 生效
eda.pcb_Event.addMouseEventListener(listenerId, 'all', () => {}, false);
// 3. 注册后查询:应为 true
const after = eda.pcb_Event.isEventListenerAlreadyExist(listenerId);
console.log('after:', after);
// 4. 移除后查询:应回到 false
eda.pcb_Event.removeEventListener(listenerId);
const afterRemove = eda.pcb_Event.isEventListenerAlreadyExist(listenerId);
console.log('afterRemove:', afterRemove);1
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