javascript-json tagged requests and articles
Categorized request examples and articles tagged with [javascript-json] keyword How do I fetch JSON using JavaScript Fetch API?
To fetch JSON from the server using the Fetch API, you need to use the JavaScript fetch() method and then call the response.json() method to get the JSON data as a JavaScript object. The response.json() method reads the data returned by the server and returns a Promise that resolves with a JSON object. If you are expecting a text, call the response.text() method. For some servers, you must also send the "Accept: application/json" header to get the response in JSON format. In this JavaScript Fetch JSON example, we retrieve a JSON from the ReqBin echo URL using the fetch() method. Click Execute to run the JavaScript Fetch JSON Example online and see the result.
How do I convert object to JSON in JavaScript?
To convert a JavaScript object to JSON, you can use the JSON.stringify(value, replacer, space) method. The JSON.stringify() method serializes objects, arrays, and primitive values into a JSON data string. The optional "replacer" parameter is a function that allows you to alter the behavior of the serialization process, and the optional "space" parameter allows you to create human-readable JSON strings. If you don't pass a "space" parameter, the JSON.stringify() method will output a minified JSON. In this JavaScript Object to JSON example, we serialize the JavaScript object to JSON data string and pretty-print the generated JSON. Click Execute to run the JavaScript Object to JSON Example online and see the result.
How do I pretty print JSON in JavaScript?
To pretty-print JSON in JavaScript, you can use the JSON.stringify(obj, replacer, space) method. The third parameter of the JSON.stringify() method specifies the number of spaces to use when outputting the JSON string. If you pass a non-zero number, JSON.stringify() will generate pretty JSON with the specified number of white spaces in the JSON. If you pass 0, then JSON.stringify() will generate minified JSON. You can also pass a string instead of a number, which will be inserted instead of spaces. In this JavaScript Pretty Print JSON example, we use the JSON.stringify() method to print a JavaScript object in a human-readable format. Click Execute to run the JavaScript Pretty Print JSON example online and see the result.
How do I convert JavaScript array to JSON?
To convert a JavaScript array to a JSON data string, you can use the JSON.stringify(value, replacer, space) method. The optional replacer parameter is a function that can alter the behavior of the serialization process. And the optional space parameter is usually used to beautify the resulting JSON by specifying the white space in the output JSON. The JSON.stringify() method serializes arrays, objects, and primitive values into a JSON string. In this JavaScript Array to JSON example, we serialize a JavaScript array into a JSON string using JSON.stringify() method. Click Execute to run the JavaScript Array to JSON Example online and see the result.
How to stringify a JavaScript object to JSON string?
You can use the JSON.stringify(value, replacer, space) method to stringify a JavaScript object or value to a JSON string. The JSON.stringify() method serializes (converts to a JSON string) objects, arrays, and primitive values. The JSON.stringify() method takes three parameters. The first parameter is the object to be converted to JSON. The second optional parameter is a function that controls the behavior of the serialization process. The third optional parameter controls the spacing in the generated JSON string. In this JavaScript JSON Stringify example, we use the JSON.stringify() method to convert a JavaScript object to a JSON string. Click Execute to run the JavaScript JSON Stringify Example online and see the result.
How do I parse JSON in JavaScript?
To parse JSON string in JavaScript, you can use the JSON.parse(string, function) method. The JSON.parse() method converts (or decodes) a string containing JSON data into a JavaScript object. The JSON.parse() method takes two parameters. The first parameter is the JSON string to parse, and the optional second parameter is the function used to transform the result (see the example below). If you pass an invalid JSON to the JSON.parse() method, you will get a SyntaxError exception. In this JSON Parse Example, we use the JSON.parse() method to convert a JSON into a JavaScript object. Click Execute to run the JavaScript JSON Parse Example online and see the result.
How do I clone a JavaScript array?
You can clone a JavaScript array using the Object.assign() and array.forEach() methods, a for loop, or a spread operator (the fastest way). The Object.assign() method creates a shallow array copy of all enumerable properties from one or more source objects. The spread operator ("...") is handy and fast but has been available since ECMAScript 6 and can be used to clone JavaScript arrays by expanding them. This spread operator clones multidimensional JavaScript arrays by reference, not by value. In this JavaScript Array Cloning Example, we use the spread ("...") operator to clone an array. More JavaScript array cloning examples are shown below. Click on Execute to run JavaScript Clone Array Example online and see the results.
To fetch JSON from the server using the Fetch API, you need to use the JavaScript fetch() method and then call the response.json() method to get the JSON data as a JavaScript object. The response.json() method reads the data returned by the server and returns a Promise that resolves with a JSON object. If you are expecting a text, call the response.text() method. For some servers, you must also send the "Accept: application/json" header to get the response in JSON format. In this JavaScript Fetch JSON example, we retrieve a JSON from the ReqBin echo URL using the fetch() method. Click Execute to run the JavaScript Fetch JSON Example online and see the result.
How do I convert object to JSON in JavaScript?
To convert a JavaScript object to JSON, you can use the JSON.stringify(value, replacer, space) method. The JSON.stringify() method serializes objects, arrays, and primitive values into a JSON data string. The optional "replacer" parameter is a function that allows you to alter the behavior of the serialization process, and the optional "space" parameter allows you to create human-readable JSON strings. If you don't pass a "space" parameter, the JSON.stringify() method will output a minified JSON. In this JavaScript Object to JSON example, we serialize the JavaScript object to JSON data string and pretty-print the generated JSON. Click Execute to run the JavaScript Object to JSON Example online and see the result.
How do I pretty print JSON in JavaScript?
To pretty-print JSON in JavaScript, you can use the JSON.stringify(obj, replacer, space) method. The third parameter of the JSON.stringify() method specifies the number of spaces to use when outputting the JSON string. If you pass a non-zero number, JSON.stringify() will generate pretty JSON with the specified number of white spaces in the JSON. If you pass 0, then JSON.stringify() will generate minified JSON. You can also pass a string instead of a number, which will be inserted instead of spaces. In this JavaScript Pretty Print JSON example, we use the JSON.stringify() method to print a JavaScript object in a human-readable format. Click Execute to run the JavaScript Pretty Print JSON example online and see the result.
How do I convert JavaScript array to JSON?
To convert a JavaScript array to a JSON data string, you can use the JSON.stringify(value, replacer, space) method. The optional replacer parameter is a function that can alter the behavior of the serialization process. And the optional space parameter is usually used to beautify the resulting JSON by specifying the white space in the output JSON. The JSON.stringify() method serializes arrays, objects, and primitive values into a JSON string. In this JavaScript Array to JSON example, we serialize a JavaScript array into a JSON string using JSON.stringify() method. Click Execute to run the JavaScript Array to JSON Example online and see the result.
How to stringify a JavaScript object to JSON string?
You can use the JSON.stringify(value, replacer, space) method to stringify a JavaScript object or value to a JSON string. The JSON.stringify() method serializes (converts to a JSON string) objects, arrays, and primitive values. The JSON.stringify() method takes three parameters. The first parameter is the object to be converted to JSON. The second optional parameter is a function that controls the behavior of the serialization process. The third optional parameter controls the spacing in the generated JSON string. In this JavaScript JSON Stringify example, we use the JSON.stringify() method to convert a JavaScript object to a JSON string. Click Execute to run the JavaScript JSON Stringify Example online and see the result.
How do I parse JSON in JavaScript?
To parse JSON string in JavaScript, you can use the JSON.parse(string, function) method. The JSON.parse() method converts (or decodes) a string containing JSON data into a JavaScript object. The JSON.parse() method takes two parameters. The first parameter is the JSON string to parse, and the optional second parameter is the function used to transform the result (see the example below). If you pass an invalid JSON to the JSON.parse() method, you will get a SyntaxError exception. In this JSON Parse Example, we use the JSON.parse() method to convert a JSON into a JavaScript object. Click Execute to run the JavaScript JSON Parse Example online and see the result.
How do I clone a JavaScript array?
You can clone a JavaScript array using the Object.assign() and array.forEach() methods, a for loop, or a spread operator (the fastest way). The Object.assign() method creates a shallow array copy of all enumerable properties from one or more source objects. The spread operator ("...") is handy and fast but has been available since ECMAScript 6 and can be used to clone JavaScript arrays by expanding them. This spread operator clones multidimensional JavaScript arrays by reference, not by value. In this JavaScript Array Cloning Example, we use the spread ("...") operator to clone an array. More JavaScript array cloning examples are shown below. Click on Execute to run JavaScript Clone Array Example online and see the results.