query-string
Parse and stringify URL query strings
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Install
$ npm install query-string
Usage
const queryString = require('query-string');
console.log(location.search);
//=> '?foo=bar'
const parsed = queryString.parse(location.search);
console.log(parsed);
//=> {foo: 'bar'}
console.log(location.hash);
//=> '#token=bada55cafe'
const parsedHash = queryString.parse(location.hash);
console.log(parsedHash);
//=> {token: 'bada55cafe'}
parsed.foo = 'unicorn';
parsed.ilike = 'pizza';
const stringified = queryString.stringify(parsed);
//=> 'foo=unicorn&ilike=pizza'
location.search = stringified;
// note that `location.search` automatically prepends a question mark
console.log(location.search);
//=> '?foo=unicorn&ilike=pizza'
API
.parse(string, [options])
Parse a query string into an object. Leading ?
or #
are ignored, so you can pass location.search
or location.hash
directly.
The returned object is created with Object.create(null)
and thus does not have a prototype
.
URI components are decoded with decode-uri-component
.
arrayFormat
Type: string
Default: 'none'
Supports both index
for an indexed array representation or bracket
for a bracketed array representation.
bracket
: stands for parsing correctly arrays with bracket representation on the query string, such as:
queryString.parse('foo[]=1&foo[]=2&foo[]=3', {arrayFormat: 'bracket'});
//=> foo: [1,2,3]
index
: stands for parsing taking the index into account, such as:
queryString.parse('foo[0]=1&foo[1]=2&foo[3]=3', {arrayFormat: 'index'});
//=> foo: [1,2,3]
none
: is the default option and removes any bracket representation, such as:
queryString.parse('foo=1&foo=2&foo=3');
//=> foo: [1,2,3]
.stringify(object, [options])
Stringify an object into a query string, sorting the keys.
strict
Type: boolean
Default: true
Strictly encode URI components with strict-uri-encode. It uses encodeURIComponent if set to false. You probably don't care about this option.
encode
Type: boolean
Default: true
URL encode the keys and values.
arrayFormat
Type: string
Default: 'none'
Supports both index
for an indexed array representation or bracket
for a bracketed array representation.
bracket
: stands for parsing correctly arrays with bracket representation on the query string, such as:
queryString.stringify({foo: [1,2,3]}, {arrayFormat: 'bracket'});
// => foo[]=1&foo[]=2&foo[]=3
index
: stands for parsing taking the index into account, such as:
queryString.stringify({foo: [1,2,3]}, {arrayFormat: 'index'});
// => foo[0]=1&foo[1]=2&foo[3]=3
none
: is the default option and removes any bracket representation, such as:
queryString.stringify({foo: [1,2,3]});
// => foo=1&foo=2&foo=3
.extract(string)
Extract a query string from a URL that can be passed into .parse()
.
Nesting
This module intentionally doesn't support nesting as it's not spec'd and varies between implementations, which causes a lot of edge cases.
You're much better off just converting the object to a JSON string:
queryString.stringify({
foo: 'bar',
nested: JSON.stringify({
unicorn: 'cake'
})
});
//=> 'foo=bar&nested=%7B%22unicorn%22%3A%22cake%22%7D'
However, there is support for multiple instances of the same key:
queryString.parse('likes=cake&name=bob&likes=icecream');
//=> {likes: ['cake', 'icecream'], name: 'bob'}
queryString.stringify({color: ['taupe', 'chartreuse'], id: '515'});
//=> 'color=chartreuse&color=taupe&id=515'
Falsy values
Sometimes you want to unset a key, or maybe just make it present without assigning a value to it. Here is how falsy values are stringified:
queryString.stringify({foo: false});
//=> 'foo=false'
queryString.stringify({foo: null});
//=> 'foo'
queryString.stringify({foo: undefined});
//=> ''
License
MIT © Sindre Sorhus