INPUT
[
{"Id":1,"text":"Welcome","question":"san","translation":"willkommen."},
{"Id":1,"text":"Welcome","question":"se","translation":"bienvenida"},
{"Id":1,"text":"Welcome","question":"fr","translation":"propriétaires"},
{"Id":1,"text":"ajax","question":"san","translation":"ommen."},
{"Id":1,"text":"ajax","question":"se","translation":"bienve"},
{"Id":1,"text":"ajax","question":"fr","translation":"propires"}
]
if question = san then all "san" objects will be inserted in array like and so on-
san:[{"text":"Welcome","question":"san","translation":"willkommen.},
{"text":"ajax","question":"san","translation":"ommen."},
se:[{"text":"Welcome","question":"se","translation":"bienvenida.},
{"text":"ajax","question":"se","translation":"bienve."},
fr:[{"text":"Welcome","question":"fr","translation":"propriétaires.},
{"text":"ajax","question":"fr","translation":"propires."},
Question is how do i check if question=san then make one array and insert all san values in it and so on without hardcoding the question property values.
Tried looping things but how to match without hardcoding because in future question attribute can change .
question="san" will be all together in an array "se" will be all together in an array and so on.
New to this not know much about nodejs.
Tried something like this but not coming as required way
fs.readFile('./data.json', 'utf8', function (err,data) {
data = JSON.parse(data);
var array = [];
for(var i = 0; i < data.length; i++) {
var lang = data[i].language;
for(var j= 0; j< data.length; j++) {
if(lang == data[j].language){
array.push(data[j].language);
array.push(data[j].translation);
array.push(data[j].text);
}
}
}
output Required
san:[{"text":"Welcome","question":"san","translation":"willkommen.},
{"text":"ajax","question":"san","translation":"ommen."},
se:[{"text":"Welcome","question":"se","translation":"bienvenida.},
{"text":"ajax","question":"se","translation":"bienve."},
fr:[{"text":"Welcome","question":"fr","translation":"propriétaires.},
{"text":"ajax","question":"fr","translation":"propires."},
I recommend you to use ES6 functions instead of for. You can separate the different processes and make the code more modular and declarative. This way you can change easily the desired output since your code is made by little pieces.
const data = [
{"Id":1,"text":"hi all present ","language":"sde","translation":"Hernjd ndjjsjdj"},
{"Id":1,"text":"hi all present","language":"ses","translation":"dfks kdfk kdfk"},
{"Id":1,"text":"hi all present","language":"sfr","translation":"bsh kkoweofeo"},
{"Id":1,"text":"hi all present","language":"szh","translation":"kdijo keow"},
{"Id":1,"text":"activated","language":"sde","translation":"Konto eid ke"},
{"Id":1,"text":"activated","language":"ses","translation":"La cueweffewfefwef."},
{"Id":1,"text":"activated","language":"sfr","translation":"Cowefrwef"},
{"Id":1,"text":"activated","language":"szh","translation":"fhewjhfwh"},
{"Id":1,"text":"completed","language":"sde","translation":"Ihr fwejiewf"},
{"Id":1,"text":"completed","language":"ses","translation":"Ya hfuwifrw"},
{"Id":1,"text":"completed","language":"sfr","translation":"Votrkwfwe"},
{"Id":1,"text":"completed","language":"szh","translation":"dmksfkwkf"},
{"Id":1,"text":"ACTION","language":"sde","translation":"AKTION"},
{"Id":1,"text":"ACTION","language":"ses","translation":"ACCIONES"},
{"Id":1,"text":"ACTION","language":"fr","translation":"ACTION"}];
// Define the properties that we want to filter for each element
const filterProperties = (item) => ({
text:item.text,
language: item.language,
translation:item.translation
})
// Given a type of languages ('sde'), filter the data in function of this value
const getItemsByLanguage = (language) => {
return data.filter((item) => item.language === language)
}
const onlyUnique = (value, index, self) => {
return self.indexOf(value) === index;
}
// Get the unique values of languages: ['sde', 'ses', 'sfr', ...]
const uniqueLanguages = data.map((item) => item.language).filter(onlyUnique)
// Get all found items for a language ('sde') and get the desired format (returns array of objects)
const resultArray = uniqueLanguages.map((language) => (
{[language]: getItemsByLanguage(language).map(filterProperties)}
))
// Convert the array of objects to single object
const result = Object.assign({}, ...resultArray)
console.log(result)
const data = [
{"Id":1,"text":"hi all present ","language":"sde","translation":"Hernjd ndjjs
jdj"},
{"Id":1,"text":"hi all present","language":"ses","translation":"dfks kdfk
kdfk"},
{"Id":1,"text":"hi all present","language":"sfr","translation":"bsh kkowe
ofeo"},
{"Id":1,"text":"hi all present","language":"szh","translation":"kdijo keow"},
{"Id":1,"text":"activated","language":"sde","translation":"Konto eid ke"},
{"Id":1,"text":"activated","language":"ses","translation":"La cueweffewfef
wef."},
{"Id":1,"text":"activated","language":"sfr","translation":"Cowefrwef"},
{"Id":1,"text":"activated","language":"szh","translation":"fhewjhfwh"},
{"Id":1,"text":"completed","language":"sde","translation":"Ihr fwejiewf"},
{"Id":1,"text":"completed","language":"ses","translation":"Ya hfuwifrw"},
{"Id":1,"text":"completed","language":"sfr","translation":"Votrkwfwe"},
{"Id":1,"text":"completed","language":"szh","translation":"dmksfkwkf"},
{"Id":1,"text":"ACTION","language":"sde","translation":"AKTION"},
{"Id":1,"text":"ACTION","language":"ses","translation":"ACCIONES"},
{"Id":1,"text":"ACTION","language":"fr","translation":"ACTION"}];
// Define the properties that we want to filter for each element
const filterProperties = (data) => ({
text:data.text,
question: data.question,
translation:data.translation
})
// Given a type of question ('san'), filter the data in function of this value
const getQuestions = (question) => {
return data.filter((item) => item.question === question)
}
const onlyUnique = (value, index, self) => {
return self.indexOf(value) === index;
}
// Get the unique values of questions: ['san', 'se', 'fr']
const uniqueQuestions = data.map((item) => item.question).filter(onlyUnique)
// Get all found values for a question and get the desired format (returns
array of objects)
const resultArray = uniqueQuestions.map((question) => (
{[question]: getQuestions(question).map(filterProperties)}
))
// Convert the array of objects to single object
const result = Object.assign({}, ...resultArray)
console.log(result)
I came across a youtube video showing how to count each letters' occurrence using Javascript, eg when the input is "hello", the function will return
{h:1 e:1 l:2 o:1}
Like this:
const obj = {};
for (let i = 0; i < wordInput.length; i++) {
const char = wordInput[i];
if (!obj[char]) {
obj[char] = 0;
}
obj[char]++;
}
Why do we need the if statement? He said something like "some of these are undefined", but I'm not really sure what that means, can you explain why we need the if (!obj[char])?
In the first run of the loop
i = 0
-----------
char = 'h'
obj = {}
obj[char] ==> obj['h'] ==> undefined
So if you try to do
obj[char]++ ==> obj['h']++ , it will throw error as the value is undefined. Instead initialize it to 0 first, using the if statement, then increment it.
The obj object starts out empty. Trying to access any property of it will return undefined, and if you try to use ++ on undefined, you'll get NaN (Not a Number), which is not what you want:
const obj = {};
obj.foo++;
console.log(obj.foo);
To fix that, before incrementing, check to see if the property exists first, and if it doesn't, set it to 0. 0 is incrementable; undefined is not.
const obj = {};
if (!obj.foo) {
obj.foo = 0;
}
obj.foo++;
console.log(obj.foo);
The code in your question does the same sort of thing, except it iterates over chars (characters of the wordInput string). If the character hasn't been put as a property of the object yet, it must be set before incrementing, otherwise the resulting object will contain useless NaN values:
const wordInput = 'foo bar';
const obj = {};
for (let i = 0; i < wordInput.length; i++) {
const char = wordInput[i];
obj[char]++;
}
console.log(obj);
The if statement is for the first entry of a character. Before 'a' comes, there's no property in obj called 'a'. So obj[char] defines a property and sets its value to 0. Before that, there's no property, so it's undefined. You can't apply operator to undefined.
This is how obj looks like when the first letter comes in 'hello'
before the if statement:
obj = {};
so obj['h'] = undefined;
It enters the if statement, then:
obj = { 'h' : 0 }
Take this object:
x = {
"key1": "xxx",
"key2": function(){return this.key1}
}
If I do this:
y = JSON.parse( JSON.stringify(x) );
Then y will return { "key1": "xxx" }. Is there anything one could do to transfer functions via stringify? Creating an object with attached functions is possible with the "ye goode olde eval()", but whats with packing it?
json-stringify-function is a similar post to this one.
A snippet discovered via that post may be useful to anyone stumbling across this answer. It works by making use of the replacer parameter in JSON.stringify and the reviver parameter in JSON.parse.
More specifically, when a value happens to be of type function, .toString() is called on it via the replacer. When it comes time to parse, eval() is performed via the reviver when a function is present in string form.
var JSONfn;
if (!JSONfn) {
JSONfn = {};
}
(function () {
JSONfn.stringify = function(obj) {
return JSON.stringify(obj,function(key, value){
return (typeof value === 'function' ) ? value.toString() : value;
});
}
JSONfn.parse = function(str) {
return JSON.parse(str,function(key, value){
if(typeof value != 'string') return value;
return ( value.substring(0,8) == 'function') ? eval('('+value+')') : value;
});
}
}());
Code Snippet taken from Vadim Kiryukhin's JSONfn.js or see documentation at Home Page
I've had a similar requirement lately. To be clear, the output looks like JSON but in fact is just javascript.
JSON.stringify works well in most cases, but "fails" with functions.
I got it working with a few tricks:
make use of replacer (2nd parameter of JSON.stringify())
use func.toString() to get the JS code for a function
remember which functions have been stringified and replace them directly in the result
And here's how it looks like:
// our source data
const source = {
"aaa": 123,
"bbb": function (c) {
// do something
return c + 1;
}
};
// keep a list of serialized functions
const functions = [];
// json replacer - returns a placeholder for functions
const jsonReplacer = function (key, val) {
if (typeof val === 'function') {
functions.push(val.toString());
return "{func_" + (functions.length - 1) + "}";
}
return val;
};
// regex replacer - replaces placeholders with functions
const funcReplacer = function (match, id) {
return functions[id];
};
const result = JSON
.stringify(source, jsonReplacer) // generate json with placeholders
.replace(/"\{func_(\d+)\}"/g, funcReplacer); // replace placeholders with functions
// show the result
document.body.innerText = result;
body { white-space: pre-wrap; font-family: monospace; }
Important: Be careful about the placeholder format - make sure it's not too generic. If you change it, also change the regex as applicable.
Technically this is not JSON, I can also hardly imagine why would you want to do this, but try the following hack:
x.key2 = x.key2.toString();
JSON.stringify(x) //"{"key1":"xxx","key2":"function (){return this.key1}"}"
Of course the first line can be automated by iterating recursively over the object. Reverse operation is harder - function is only a string, eval will work, but you have to guess whether a given key contains a stringified function code or not.
You can't pack functions since the data they close over is not visible to any serializer.
Even Mozilla's uneval cannot pack closures properly.
Your best bet, is to use a reviver and a replacer.
https://yuilibrary.com/yui/docs/json/json-freeze-thaw.html
The reviver function passed to JSON.parse is applied to all key:value pairs in the raw parsed object from the deepest keys to the highest level. In our case, this means that the name and discovered properties will be passed through the reviver, and then the object containing those keys will be passed through.
This is what I did https://gist.github.com/Lepozepo/3275d686bc56e4fb5d11d27ef330a8ed
function stringifyWithFunctions(object) {
return JSON.stringify(object, (key, val) => {
if (typeof val === 'function') {
return `(${val})`; // make it a string, surround it by parenthesis to ensure we can revive it as an anonymous function
}
return val;
});
};
function parseWithFunctions(obj) {
return JSON.parse(obj, (k, v) => {
if (typeof v === 'string' && v.indexOf('function') >= 0) {
return eval(v);
}
return v;
});
};
The naughty but effective way would be to simply:
Function.prototype.toJSON = function() { return this.toString(); }
Though your real problem (aside from modifying the prototype of Function) would be deserialization without the use of eval.
I have come up with this solution which will take care of conversion of functions (no eval). All you have to do is put this code before you use JSON methods. Usage is exactly the same but right now it takes only one param value to convert to a JSON string, so if you pass remaning replacer and space params, they will be ignored.
void function () {
window.JSON = Object.create(JSON)
JSON.stringify = function (obj) {
return JSON.__proto__.stringify(obj, function (key, value) {
if (typeof value === 'function') {
return value.toString()
}
return value
})
}
JSON.parse = function (obj) {
return JSON.__proto__.parse(obj, function (key, value) {
if (typeof value === 'string' && value.slice(0, 8) == 'function') {
return Function('return ' + value)()
}
return value
})
}
}()
// YOUR CODE GOES BELOW HERE
x = {
"key1": "xxx",
"key2": function(){return this.key1}
}
const y = JSON.parse(JSON.stringify(x))
console.log(y.key2())
It is entirely possible to create functions from string without eval()
var obj = {a:function(a,b){
return a+b;
}};
var serialized = JSON.stringify(obj, function(k,v){
//special treatment for function types
if(typeof v === "function")
return v.toString();//we save the function as string
return v;
});
/*output:
"{"a":"function (a,b){\n return a+b;\n }"}"
*/
now some magic to turn string into function with this function
var compileFunction = function(str){
//find parameters
var pstart = str.indexOf('('), pend = str.indexOf(')');
var params = str.substring(pstart+1, pend);
params = params.trim();
//find function body
var bstart = str.indexOf('{'), bend = str.lastIndexOf('}');
var str = str.substring(bstart+1, bend);
return Function(params, str);
}
now use JSON.parse with reviver
var revivedObj = JSON.parse(serialized, function(k,v){
// there is probably a better way to determ if a value is a function string
if(typeof v === "string" && v.indexOf("function") !== -1)
return compileFunction(v);
return v;
});
//output:
revivedObj.a
function anonymous(a,b
/**/) {
return a+b;
}
revivedObj.a(1,2)
3
To my knowledge, there are no serialization libraries that persist functions - in any language. Serialization is what one does to preserve data. Compilation is what one does to preserve functions.
It seems that people landing here are dealing with structures that would be valid JSON if not for the fact that they contain functions. So how do we handle stringifying these structures?
I ran into the problem while writing a script to modify RequireJS configurations. This is how I did it. First, there's a bit of code earlier that makes sure that the placeholder used internally (">>>F<<<") does not show up as a value in the RequireJS configuration. Very unlikely to happen but better safe than sorry. The input configuration is read as a JavaScript Object, which may contain arrays, atomic values, other Objects and functions. It would be straightforwardly stringifiable as JSON if functions were not present. This configuration is the config object in the code that follows:
// Holds functions we encounter.
var functions = [];
var placeholder = ">>>F<<<";
// This handler just records a function object in `functions` and returns the
// placeholder as the value to insert into the JSON structure.
function handler(key, value) {
if (value instanceof Function) {
functions.push(value);
return placeholder;
}
return value;
}
// We stringify, using our custom handler.
var pre = JSON.stringify(config, handler, 4);
// Then we replace the placeholders in order they were encountered, with
// the functions we've recorded.
var post = pre.replace(new RegExp('"' + placeholder + '"', 'g'),
functions.shift.bind(functions));
The post variable contains the final value. This code relies on the fact that the order in which handler is called is the same as the order of the various pieces of data in the final JSON. I've checked the ECMAScript 5th edition, which defines the stringification algorithm and cannot find a case where there would be an ordering problem. If this algorithm were to change in a future edition the fix would be to use unique placholders for function and use these to refer back to the functions which would be stored in an associative array mapping unique placeholders to functions.