从 jQuery 或 JS 中的 json 对象中提取数据

Question

I want to use the currency data provided by https://raw.github.com/currencybot/open-exchange-rates/master/latest.json

As an initial test, I've created a cut-down version of this as an inline object:

var obj = [
{
    "disclaimer": "This data is collected from various providers and provided free of charge for informational purposes only, with no guarantee whatsoever of accuracy, validity, availability, or fitness for any purpose; use at your own risk. Other than that, have fun! More info: http://openexchangerates.org/terms/",
    "license": "Data collected from various providers with public-facing APIs; copyright may apply; not for resale; no warranties given. Full license info: http://openexchangerates.org/license/",
    "timestamp": 1339036116,
    "base": "USD",
    "rates": {
        "EUR": 0.795767,
        "GBP": 0.645895,
        "JPY": 79.324997,
        "USD": 1
    }
}];

All I want to be able to do is somehow query/grep/filter the json object with, for example, "EUR" as the criteria and have it return a variable called 'rate' with a value of '0.795767' as a result.

I've looked at the JQuery grep and filter functions but I can't figure out how to isolate just the 'rates' section of the object and then to get the rate I want.

Answer 1

var obj = [
{
    "disclaimer": "This data is collected from various providers and provided free of charge for informational purposes only, with no guarantee whatsoever of accuracy, validity, availability, or fitness for any purpose; use at your own risk. Other than that, have fun! More info: http://openexchangerates.org/terms/",
    "license": "Data collected from various providers with public-facing APIs; copyright may apply; not for resale; no warranties given. Full license info: http://openexchangerates.org/license/",
    "timestamp": 1339036116,
    "base": "USD",
    "rates": {
        "EUR": 0.795767,
        "GBP": 0.645895,
        "JPY": 79.324997,
        "USD": 1
    }
}];

obj[0].rates.EUR; // output: 0.795767

or

obj[0].rates['EUR']; output: //0.795767

DEMO

If you want to isolate rates in another variable and use that variable then try like following:

var rates = obj[0].rates;

Now,

rates.EUR;
rates.GBP;

and so on.

Answer 2

You can also use JSON.parse() function of Javascript to convert JSON String into Javascript JSON object.

var JSONObject = JSON.parse("{'value1' : 1, 'value2' : 2}");
console.log(JSONObject.value1);  // Prints '1'..

Answer 3

data contains FRELD6 try to :

var reldte;
var sdata = JSON.parse(data);
 $(sdata).each(function () {
        reldte = RefineDate(this.FRELD6.toString());
}