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并发请求池 ​

参考文章：如何使用JavaScript实现一个带有并发限制的请求池？请提供详细的操作步骤和示例代码

js
const getRandomIntInclusive = (min, max) => {
    min = Math.ceil(min);
    max = Math.floor(max);
    return Math.floor(Math.random() * (max - min + 1)) + min; //含最大值，含最小值
};

const delay = async (time) => {
    await new Promise((resolve) => {
        setTimeout(resolve, time);
    });
};

module.exports = class RequestPool {
    constructor(poolSize) {
        this.poolSize = poolSize;
        this.running = 0;
        this.queue = [];
    }
    async addRequest(request) {
        await delay(getRandomIntInclusive(0, 1000));
        if (this.running > this.poolSize) {
            await new Promise((resolve) => {
                this.queue.push(resolve);
            });
        }
        this.running++;
        const response = await request();
        this.running--;
        if (this.queue.length > 0) {
            this.queue.shift()();
        }
        return response;
    }
};
const getRandomIntInclusive = (min, max) => {
    min = Math.ceil(min);
    max = Math.floor(max);
    return Math.floor(Math.random() * (max - min + 1)) + min; //含最大值，含最小值
};

const delay = async (time) => {
    await new Promise((resolve) => {
        setTimeout(resolve, time);
    });
};

module.exports = class RequestPool {
    constructor(poolSize) {
        this.poolSize = poolSize;
        this.running = 0;
        this.queue = [];
    }
    async addRequest(request) {
        await delay(getRandomIntInclusive(0, 1000));
        if (this.running > this.poolSize) {
            await new Promise((resolve) => {
                this.queue.push(resolve);
            });
        }
        this.running++;
        const response = await request();
        this.running--;
        if (this.queue.length > 0) {
            this.queue.shift()();
        }
        return response;
    }
};

js获取input元素，给value赋值无效 ​

原因是这个页面使用了一些前端框架，比如vue。在进行数据双向绑定之后，我们使用js原生获取dom的方式去求改input元素的value值，双向绑定的机制不能检测到数据修改，因为双向绑定是通过事件进行修改数据的。

解决方法： 在修改input元素的value后，要抛出事件，来让双向绑定框架捕获到数据的修改。

js
const userNameInput = document.querySelector('input[name="username"]');
userNameInput.value = "username";
userNameInput.dispatchEvent(new Event("input"));
const userNameInput = document.querySelector('input[name="username"]');
userNameInput.value = "username";
userNameInput.dispatchEvent(new Event("input"));