模块和require()

时间:2019-02-07 17:10:58

标签: javascript mysql node.js

我有两个文件,一个位于1.js之间,另一个是import.js。 在between1.js中,我只有几个功能,而其中一个功能已移至import.js。我得到的练习是使用模块并需要功能。我仍然有如何在between1.js中使用require的问题。参见下面的代码

Between1.js代码: https://codeshare.io/alxMvY

import.js: https://codeshare.io/244yg4

我是js和node的初学者。我在import.js中获得了函数,并且在代码底部是module.exports,这意味着要导出模块,并且在1.js之间的第二个文件中,我尝试首先导入该函数: 让utils = require(“ ./ import.js”); 在底部尝试获取功能,但是问题是我真的不知道如何。我试图像在代码中粘贴之前一样,但这没用

我想要的是有人帮助我解释如何要求和模块工作。

import.js代码:

    /**
 * Module.
 *
 * Matteus Urbaniak
 */
 "use strict";


function teacherAsTable(res) {
     let str;

     str = "+-----------+---------------------+-----------+----------+--------------+\n";
     str += "| Akronym   | Namn                | Avdelning |   Lön    | Kompetens    |\n";
     str += "|-----------|---------------------|-----------|----------|--------------|\n";
     for (const row of res) {
         str += "| ";
         str += row.akronym.padEnd(10);
         str += "| ";
         str += (row.fornamn + " " + row.efternamn).padEnd(20);
         str += "| ";
         str += row.avdelning.padEnd(10);
         str += "| ";
         str += row.lon.toString().padStart(9);
         str += "| ";
         str += row.kompetens.toString().padEnd(12);
         str += " |\n";
     }
     str += "+-----------+---------------------+-----------+----------+--------------|\n";

     return str;
 }

module.exports = {
    "teacherAsTable": teacherAsTable
};

between1.js

    /**
Arbete gjordes av Matteus Urbaniak
*/


"use strict";


/**
Jag använder programmeringsstilen med async/await
för att hantera asynkrona anrop. För det syftet väljer
jag paketet promise-mysql som är en wrapper kring paketet mysql.
*/

const mysql = require("promise-mysql");

// Inloggningsdetaljer till databasen.
const config = require("./config.json");

let utils = require("./import.js");

// Läsa från komand linje

const readline = require('readline');
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

/**
Main function
*/

(async function() {
    const db = await mysql.createConnection(config);
    let str;

    rl.question("What do you want search for? (min); ", async (min) => {
        rl.question("What do you want search for? (max); ", async (max) => {
            str = await searchBetween(db, min, max);
            console.info(str);
            rl.close();
            db.end();
        });
    });
})();



// Ge en rapport med larare details och formaterad text.

async function searchBetween(db, min, max) {
    let sql;
    let res;
    let str;
    let minimum = `${min}`;
    let maximum = `${max}`;

    console.info(`Searching for: ${minimum} - ${maximum}`);
    sql = `
        SELECT
            akronym,
            fornamn,
            efternamn,
            avdelning,
            lon,
            kompetens
        FROM larare
        WHERE
            (kompetens BETWEEN ? AND ?)
            OR
            lon BETWEEN ? AND ?
        ORDER BY akronym;
    `;
    res = await db.query(sql, [minimum, maximum, minimum, maximum]);
    str = teacherAsTable(res);
    return str;
}

// HERE SHOULD BE teacherAsTable 
let res;

res = utils.teacherAsTable();
console.log(res);

1 个答案:

答案 0 :(得分:0)

尝试在Between1.js中执行此操作:

module.exports = {teacherAsTable};