node 连接 mongodb 并简单实现增删改查

let MongoClient = require("mongodb").MongoClient;
let url = "mongodb://192.168.200.100:27017/admin";

MongoClient.connect(url, function (err, db) {
    if (err) {
        console.log("数据库连接失败!");
    } else {
        /* 验证账号密码, 每个库都会有自己的账号密码, 超级用户也不能访问所有的 */
        db.authenticate("root", "920619", function () {
            insertOne(db);
        });
    }
});

function insertOne(db) {
    db.collection("User").insertOne({
        "name": "测试二",
        "sex": 0
    }, function (err, result) {
        console.log(result.result);
        console.log(result.ops)
        db.close();
    });
}

let MongoClient = require("mongodb").MongoClient;
let ObjectId = require("mongodb").ObjectID;
let url = "mongodb://192.168.200.100:27017/admin";

MongoClient.connect(url, function (err, db) {
    if (err) {
        console.log("数据库连接失败!");
    } else {
        /* 验证账号密码, 每个库都会有自己的账号密码, 超级用户也不能访问所有的 */
        db.authenticate("root", "920619", function () {
            deleteData(db);
        });
    }
});

function deleteData(db) {
    db.collection("User").deleteOne({
        _id: new ObjectId("59ba30e093f3501f8c8c468e")
    }, function (err, result) {
        console.log(result.result);
        db.close();
    });
}

let MongoClient = require("mongodb").MongoClient;
let url = "mongodb://192.168.200.100:27017/admin";

MongoClient.connect(url, function (err, db) {
    if (err) {
        console.log("数据库连接失败!");
    } else {
        /* 验证账号密码, 每个库都会有自己的账号密码, 超级用户也不能访问所有的 */
        db.authenticate("root", "920619", function () {
            uodateData(db);
        });
    }
});

function uodateData(db) {
    var cursor = db.collection("User").updateMany({
        "name": "张三"
    }, {
        "$set": {
            "name": "陈辉",
            "sex": 1
        }
    }, function (err, result) {
        console.log(result.result);
    });
}

let MongoClient = require("mongodb").MongoClient;
let ObjectId = require("mongodb").ObjectID;
let url = "mongodb://192.168.200.100:27017/admin";

MongoClient.connect(url, function (err, db) {
    if (err) {
        console.log("数据库连接失败!");
    } else {
        /* 验证账号密码, 每个库都会有自己的账号密码, 超级用户也不能访问所有的 */
        db.authenticate("root", "920619", function () {
            selectAll(db)
        });
    }
});

function selectAll(db) {
    // 精确查找
    // var cursor = db.collection("User").find({_id: new ObjectId("59ba30970692cd172083a836")});
    // 查询全部
    var cursor = db.collection("User").find();
    var result = [];
    cursor.each(function (err, doc) {
        if (doc == null) {
            console.log(result);
            db.close();
        } else {
            result.push(doc);
        }
    });
}