JS中同步心得

不使用co模块

异步代码

getProjectProfile() {
    console.log("2");
    return new Promise(function (resolve, reject) {
        console.log("3");
        Editor.Profile.load('profile://project/project.json', (error, profile) => {
            console.log("4");
            if (error) {
                return reject(error);
            }
            resolve(profile);
            return profile;
        });
    });
},

2种方式

• then 实现同步

console.log("1");
this.getProjectProfile().then(profile => {
    console.log(profile);
});
console.log("5");

• async 实现同步

(async ()=>{
    console.log("1");
    let p = await this.getProjectProfile();
    console.log(p);
    console.log("5");
})();

co模块实现同步(co+yield)

异步代码

child_process.execPromise = function (cmd, options, callback) {
    return new Promise(function (resolve, reject) {
        child_process.exec(cmd, options, function (err, stdout, stderr) {
            // console.log("执行完毕!");
            if (err) {
                console.log(err);
                callback && callback(stderr);
                reject(err);
                return;
            }
            resolve();
        })
    });
};

co(function(){
    yield child_process.execPromise(cmd, null, function (err) {
        this._addLog("出现错误: \n" + err);
    }.bind(this));
});