book-hi/utils/event-bus.js

export const eventBus = {
    events: {},

    // 注册事件监听
    on(eventName, callback) {
        if (!this.events[eventName]) {
            this.events[eventName] = [];
        }
        this.events[eventName].push(callback);
    },

    // 触发事件
    emit(eventName, data) {
        const callbacks = this.events[eventName] || [];
        callbacks.forEach((callback) => {
            if (typeof callback === "function") {
                callback(data);
            }
        });
    },

    // 移除事件监听
    off(eventName, callback) {
        const callbacks = this.events[eventName];
        if (!callbacks) return;

        if (!callback) {
            delete this.events[eventName];
            return;
        }

        this.events[eventName] = callbacks.filter((item) => item !== callback);
        if (!this.events[eventName].length) {
            delete this.events[eventName];
        }
    }
};