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DMT_Event.isEventListenerAlreadyExist() method

Query whether the event listener exists

Signature

function isEventListenerAlreadyExist(id: string): boolean;

Parameters

Parameter	Type	Description
id	string	Event ID

Returns

boolean

Whether the event listener exists

Example

const listenerId = '嘉立创示例_tab_exist';

// 1. 注册前查询：应为 false
const before = eda.dmt_Event.isEventListenerAlreadyExist(listenerId);
console.log('before:', before);

// 2. 注册一个监听使 id 生效
eda.dmt_Event.addEditorTabEventListener(
	listenerId,
	'toggle',
	() => {}
);

// 3. 注册后查询：应为 true
const after = eda.dmt_Event.isEventListenerAlreadyExist(listenerId);
console.log('after:', after);

// 4. 移除后查询：应回到 false
eda.dmt_Event.removeEventListener(listenerId);
const afterRemove = eda.dmt_Event.isEventListenerAlreadyExist(listenerId);
console.log('afterRemove:', afterRemove);