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QML Global Object Writing QML Modules

List of JavaScript Objects and Functions

This reference contains a list of objects, functions and properties supported by the JavaScript engine in Qt. For a detailed description, see the ECMA-262 specification.

The Global Object

Value Properties

  • NaN
  • Infinity
  • undefined

Function Properties

  • eval(x)
  • parseInt(string, radix)
  • parseFloat(string)
  • isNaN(number)
  • isFinite(number)
  • decodeURI(encodedURI)
  • decodeURIComponent(encodedURIComponent)
  • encodeURI(uri)
  • encodeURIComponent(uriComponent)
  • escape(string)
  • unescape(string)

Constructor Properties

  • Object
  • Function
  • Array
  • ArrayBuffer
  • String
  • Boolean
  • Number
  • DataView
  • Date
  • Promise
  • RegExp
  • Map
  • WeakMap
  • Set
  • WeakSet
  • SharedArrayBuffer
  • Symbol
  • Error
  • EvalError
  • RangeError
  • ReferenceError
  • SyntaxError
  • TypeError
  • URIError

Other Properties

  • Atomics
  • Math
  • JSON
  • Reflect
  • Proxy

The Object Object

Object Constructor

Function Properties

  • getPrototypeOf(O)
  • setPrototypeOf(O, P)
  • getOwnPropertyDescriptor(O, P)
  • getOwnPropertyDescriptors(O)
  • getOwnPropertyNames(O)
  • getOwnPropertySymbols(O)
  • assign(O [, Properties])
  • create(O [, Properties])
  • defineProperty(O, P, Attributes)
  • defineProperties(O, Properties)
  • entries(O)
  • is(V1, V2)
  • keys(O)
  • values(O)
  • seal(O)
  • isSealed(O)
  • freeze(O)
  • isFrozen(O)
  • preventExtensions(O)
  • isExtensible(O)

Object Prototype

Function Properties

  • toString()
  • toLocaleString()
  • valueOf()
  • hasOwnProperty(V)
  • isPrototypeOf(V)
  • propertyIsEnumerable(V)
  • __defineGetter__(P, F)
  • __defineSetter__(P, F)

Function Objects

Function Prototype

Function Properties

  • toString()
  • apply(thisArg, argArray)
  • call(thisArg [, arg1 [, arg2, ...]])
  • bind((thisArg [, arg1 [, arg2, …]])
  • [Symbol.hasInstance](O)

Array Objects

Array Prototype Object

Function Properties

  • toString()
  • toLocaleString()
  • concat([item1 [, item2 [, ...]]])
  • copyWithin([item1 [, item2 [, ...]]])
  • entries()
  • fill(item [, index1 [, index2]])
  • join(separator)
  • find(callbackfn [, thisArg]) // ECMAScript 6: Added in Qt 5.9
  • findIndex(callbackfn [, thisArg]) // ECMAScript 6: Added in Qt 5.9
  • includes(item)
  • keys()
  • pop()
  • push([item1 [, item2 [, ...]]])
  • reverse()
  • shift()
  • slice(start, end)
  • sort(comparefn)
  • splice(start, deleteCount[, item1 [, item2 [, ...]]])
  • unshift([item1 [, item2 [, ...]]])
  • indexOf(searchElement [, fromIndex])
  • lastIndexOf(searchElement [, fromIndex])
  • every(callbackfn [, thisArg])
  • some(callbackfn [, thisArg])
  • forEach(callbackfn [, thisArg])
  • map(callbackfn [, thisArg])
  • filter(callbackfn [, thisArg])
  • reduce(callbackfn [, initialValue])
  • reduceRight(callbackfn [, initialValue])
  • values()
  • [Symbol.iterator]()

String Objects

String Prototype Object

Function Properties

  • toString()
  • valueOf()
  • charAt(pos)
  • charCodeAt(pos)
  • codePointAt(pos)
  • concat([string1 [, string2 [, ...]]])
  • endsWith(searchString [, endPosition ]) // ECMAScript 6: Added in Qt 5.8
  • includes(searchString [, position ]) // ECMAScript 6: Added in 5.8
  • indexOf(searchString ,position)
  • lastIndexOf(searchString, position)
  • localeCompare(that)
  • match(regexp)
  • normalize()
  • padEnd(length [, string])
  • padStart(length [, string])
  • repeat(count) // ECMAScript 6: Added in Qt 5.9
  • replace(searchValue, replaceValue)
  • search(regexp)
  • slice(start, end)
  • split(separator, limit)
  • startsWith(searchString [, position ]) // ECMAScript 6: Added in Qt 5.8
  • substr(start, length)
  • substring(start, end)
  • toLowerCase()
  • toLocaleLowerCase()
  • toUpperCase()
  • toLocaleUpperCase()
  • trim()
  • [Symbol.iterator]()

Additionally, the QML engine adds the following functions to the String prototype:

Boolean Objects

Boolean Prototype Object

Function Properties

  • toString()
  • valueOf()

Number Objects

Number Prototype Object

Function Properties

  • toString(radix)
  • toLocaleString()
  • valueOf()
  • toFixed(fractionDigits)
  • toExponential(fractionDigits)
  • toPrecision(precision)

Additionally, the QML engine adds the following functions to the Number prototype:

The Number Object

Value Properties

  • NaN
  • NEGATIVE_INFINITY
  • POSITIVE_INFINITY
  • MAX_VALUE
  • MIN_VALUE
  • EPSILON // ECMAScript 6: Added in Qt 5.8
  • MAX_SAFE_INTEGER
  • MIN_SAFE_INTEGER

Function Properties

  • isFinite(x) // ECMAScript 6: Added in Qt 5.8
  • isInteger(x)
  • isSafeInteger(x)
  • isNaN(x) // ECMAScript 6: Added in Qt 5.8

The Math Object

Value Properties

  • E
  • LN10
  • LN2
  • LOG2E
  • LOG10E
  • PI
  • SQRT1_2
  • SQRT2

Function Properties

  • abs(x)
  • acos(x)
  • acosh(x)
  • asin(x)
  • asinh(x)
  • atan(x)
  • atanh(x)
  • atan2(y, x)
  • cbrt(x)
  • ceil(x)
  • clz32(x)
  • cos(x)
  • cosh(x)
  • exp(x)
  • expm1(x)
  • floor(x)
  • fround(x)
  • hypot(x, y)
  • imul(x, y)
  • log(x)
  • log10(x)
  • log1p(x)
  • log2(x)
  • max([value1 [, value2 [, ...]]])
  • min([value1 [, value2 [, ...]]])
  • pow(x, y)
  • random()
  • round(x)
  • sign(x) // ECMAScript 6: Added in Qt 5.8
  • sin(x)
  • sinh(x)
  • sqrt(x)
  • tan(x)
  • tanh(x)
  • trunc(x)

Date Objects

Date Prototype Object

Function Properties

  • toString()
  • toDateString()
  • toTimeString()
  • toLocaleString()
  • toLocaleDateString()
  • toLocaleTimeString()
  • valueOf()
  • getTime()
  • getFullYear()
  • getUTCFullYear()
  • getMonth()
  • getUTCMonth()
  • getDate()
  • getUTCDate()
  • getDay()
  • getUTCDay()
  • getHours()
  • getUTCHours()
  • getMinutes()
  • getUTCMinutes()
  • getSeconds()
  • getUTCSeconds()
  • getMilliseconds()
  • getUTCMilliseconds()
  • getTimeZoneOffset()
  • setTime(time)
  • setMilliseconds(ms)
  • setUTCMilliseconds(ms)
  • setSeconds(sec [, ms])
  • setUTCSeconds(sec [, ms])
  • setMinutes(min [, sec [, ms]])
  • setUTCMinutes(min [, sec [, ms]])
  • setHours(hour [, min [, sec [, ms]]])
  • setUTCHours(hour [, min [, sec [, ms]]])
  • setDate(date)
  • setUTCDate(date)
  • setMonth(month [, date])
  • setUTCMonth(month [, date])
  • setYear(year)
  • setFullYear(year [, month [, date]])
  • setUTCFullYear(year [, month [, date]])
  • toUTCString()
  • toGMTString()
  • toISOString()
  • toJSON()
  • [Symbol.toPrimitive](hint)

Additionally, the QML engine adds the following functions to the Date prototype:

RegExp Objects

RegExp Prototype Object

Function Properties

  • exec(string)
  • test(string)
  • toString()

Error Objects

Error Prototype Object

Value Properties

  • name
  • message

Function Properties

  • toString()

The JSON Object

Function Properties

  • parse(text [, reviver])
  • stringify(value [, replacer [, space]])

QML Global Object Writing QML Modules

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