函式遞回建議

我正在構建一個員工跟蹤應用程式。我希望我的應用程式能夠正常作業，以便在完成各種串列選擇的每個功能后，該應用程式將再次提示您使用選項串列。我可以想到幾種方法來實作這一點，但我希望更有經驗的開發人員可以推薦哪種方法最好。謝謝！

1. 將 switch 陳述句中的所有函式都變成 Promise，然后創建一個可以呼叫自身的 Promise 鏈
2. 嘗試使用 async-await 而不是 Promise 鏈？？？
3. 匯出 prompt() 函式并在每個 lib 檔案中匯入它和所有其他相應的函式

這是應用程式的入口點

const db = require('./db/connection');
const inquirer = require('inquirer');

// response handling 
const { viewDepartments, viewRoles, viewEmployees, viewByManager, viewByDepartment } = require('./lib/viewFuncs');
const { addDepartment, addRole, addEmployee } = require('./lib/addFuncs');
const { updateRole, updateManager } = require('./lib/updateFuncs');
const { deleteDepartment, deleteRole, deleteEmployee } = require('./lib/deleteFuncs');

function prompt() {
    return inquirer.prompt({
        name: 'choice',
        type: 'list',
        message: 'What would you like to do?',
        choices: [
            'View all departments', 
            'View all roles', 
            'View all employees',
            'View employees by manager',
            'View employees by department', 
            'Add a department', 
            'Add a role',
            'Add an employee', 
            'Update an employee role',
            'Update employee manager',
            'Delete a department',
            'Delete a role',
            'Delete an employee',
            'EXIT'
        ]
    }).then(answer => {
        switch (answer.choice) {
            case 'View all departments':
                viewDepartments();
                break;
            case 'View all roles':
                viewRoles();
                break;
            case 'View all employees':
                viewEmployees();
                break;
            case 'View employees by manager':
                viewByManager();
                break;
            case 'View employees by department':
                viewByDepartment();
                break;
            case 'Add a department':
                addDepartment();
                break;
            case 'Add a role':
                addRole();
                break;
            case 'Add an employee':
                addEmployee();
                break;
            case 'Update an employee role':
                updateRole();
                break;
            case 'Update an employee manager':
                updateManager();
                break;
            case 'Delete a department':
                deleteDepartment();
                break;
            case 'Delete a role':
                deleteRole();
                break;
            case 'Delete an employee':
                deleteEmployee();
                break;
            case 'EXIT': 
                exitApp();
                break;
            default:
                break;
        }
    })
};
// connect to database 
db.connect(err => {
    if (err) throw err;
    console.log('Welcome to the employee-tracker!');
    // start the app 
    prompt();
});
// exit the app
function exitApp() {
    console.log('Thank you for using the employee-tracker!')
    db.end();
};

uj5u.com熱心網友回復：

我認為 switch 陳述句是矯枉過正的。如果您創建一個物件，其中鍵是選項，函式是值，那么它是 1:1 查找并且假設性能更高。

此外，洗掉 then 陳述句，因為我們在這里撰寫現代代碼。也祝賀實習。

const choiceObj = {
            'View all departments':viewDepartments(), 
            'View all roles':viewAllRoles(), 
            ...etc etc 
}

const prompt = async () => {
    const answer = await inquirer.prompt({
        name: 'choice',
        type: 'list',
        message: 'What would you like to do?',
        choices: choiceObj.keys() // returns an array of the object keys
    })

    if (answer) {
       choiceObj[answer]; 

       alert('answer submitted'); // UX  
       setTimeout(function(){
         prompt(); // recursion after 2s
       }, 2000);
    }
};

我可以在評論部分回答任何問題。謝謝！

標籤：javascript 节点.js es6-承诺

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