Question

我想从所有匹配中获取特定的JSON数据，比如match = 2数据。我无法获得存储在MongoDB中的必需数据。

JSON回复：

{
    "_id": "5a63051735aaddd30d1d89cc",
    "id": 1,
    "season": 2008,
    "city": "Bangalore",
    "team1": "Kolkata Knight Riders",
    "team2": "Royal Challengers Bangalore",
    "toss_winner": "Royal Challengers Bangalore",
    "toss_decision": "field",
    "result": "normal",
    "dl_applied": 0,
    "winner": "Kolkata Knight Riders",
    "win_by_runs": 140,
    "win_by_wickets": 0,
    "player_of_match": "BB McCullum",
    "venue": "M Chinnaswamy Stadium",
    "umpire1": "Asad Rauf",
    "umpire2": "RE Koertzen",
    "umpire3": ""
  }

我可以使用以下代码获取577个匹配项的所有JSON数据。

app.get('/api/matches', (req, res) =>{

    matches.find({}).then(eachOne => {

        res.json(eachOne);

    });

});

但是现在我不想获得所有匹配的JSON数据，而是希望得到匹配的JSON数据id:2我怎么能得到我尝试使用下面的代码，但它获得所有匹配的JSON数据。

app.get('/api/matches/:match_id', (req, res) =>{

    let match = req.params.id;

    matches.find({match}).then(eachOne =>{

        res.json(match);
    });

});

在matches.js中：

const mongoose = require('mongoose');

let Schema = mongoose.Schema;

const matchSchema = new Schema({

    match_id:{
        type:Number,
        required:true
    },

    season:{
        type:Number,
        required:true
    },

    city:{
        type:String,
        required:true
    },

    date:{
        type:Number
    },

    team1:{
        type:String,
        required:true
    },

    team2:{
        type:String,
        required:true
    },


    toss_winner:{
        type:String,
        required:true
    },

    toss_decision:{
        type:String,
        required:true
    },

    dl_applied:{
        type:Number
    },

    winner:{
        type:String,
        required:true
    },

    win_by_runs:{
        type:Number,
        required:true
    },

    win_by_wickets:{
        type:Number,
        required:true
    },

    player_of_match:{
        type:String,
        required:true
    },

    venue:{
        type:String,
        required:true
    },

    umpire1:{
        type:String,
        required:true
    },

    umpire2:{
        type:String,
        required:true
    },

    umpire3:{
        type:String
    }

});

const matches = mongoose.model('matches', matchSchema);

module.exports = matches;

Answer 1

您的代码几乎是正确的。您只需指定正确的查询：

app.get('/api/matches/:match_id', (req, res) =>{
    let match = req.params.match_id;
    matches.findOne({id: parseInt(match)}).then(m =>{
        res.json(m);
    });
});

还要考虑来自url的match_id是一个字符串，因此您需要检查它并转换为数字（我使用parseInt）

Answer 2

默认情况下，您必须使用bodyparser。

你做错了。

app.get('/api/matches/:match_id', (req, res) =>{



    // instead of req.params.id write req.params.match_id
   let match = req.params.match_id;

    // when you write {match} there is nothing {id : match}

    matches.find({match_id : match}).then(eachOne =>{

        res.json(eachOne);
    });

});

如何使用Nodejs从REST API获取特定的JSON数据？

2 个答案: