使用Node.js阅读MongoDb集合时遇到问题

Question

I have problems reading this collection with mongoose and Node.js:

I have one JSON inside my Collection and i try to read this with this code:

materias.find().exec(function(err1,materias){
        if(err1){console.log(err1); return next();}
        for(x=0;x<materias.length;x++){
            //console.log(materias[x].Nombre);
            //var arreglo=materias[x].Horario[0].Dia; // TRY ONE
            var arreglo=JSON.parse(materias[x].Horario[0]); // TRY TWO
            console.log(arreglo[0]);

        }
         //RESPONSE TRY ONE
         console.log(arreglo) UNDEFINED
         //RESPONSE TRY TWO
         undefined [ 
         //if I use JSON.stringify the response is {[object][object]...
enter code here

Answer 1

You don't need to parse JSON manually with mongoose.

You get undefined because you define variable arreglo inside the loop but try to access it outside of it. This should work:

materias.find().exec(function(err1,materias){
if(err1){console.log(err1); return next();}
for(x=0;x<materias.length;x++)  {        
    var arreglo = materias[x].Horario[0]; // TRY TWO
    console.log(arreglo);   
}

Answer 2

What i suppose the error is: you have database named as materias and you are using the same name for the returned collection. Try changing the return name collection to something other.

materias.find().exec(function(err1, change_name_here ){

//required code
}

Answer 3

FINALYYYYYYYYYY i fixed it changing my mongoose model I had this:

var materias=new Schema({
    Nombre:{type:String, required:true},
    Docente:{type:String, required:true},
    Horario:{type:String, required:true}

});
module.exports = materias;

and change for this:

Horario:[{Dia:String, Hora:String, Tiempo:String}]

for reading:

for(x=0;x<materias.length;x++){
                var arreglo=materias[x].Horario; // TRY TWO
                console.log(arreglo[0].Dia);

            }