From 4b1a9203c547c019fc5398082ae19a3f3d4c3efe Mon Sep 17 00:00:00 2001 From: Peter Bengtsson Date: Tue, 8 Dec 2020 14:41:15 -0500 Subject: initial commit --- .../reference/global_objects/number/index.html | 218 +++++++++++++++++++++ 1 file changed, 218 insertions(+) create mode 100644 files/bn/web/javascript/reference/global_objects/number/index.html (limited to 'files/bn/web/javascript/reference/global_objects/number/index.html') diff --git a/files/bn/web/javascript/reference/global_objects/number/index.html b/files/bn/web/javascript/reference/global_objects/number/index.html new file mode 100644 index 0000000000..a4740d7dab --- /dev/null +++ b/files/bn/web/javascript/reference/global_objects/number/index.html @@ -0,0 +1,218 @@ +--- +title: Number +slug: Web/JavaScript/Reference/Global_Objects/Number +tags: + - JavaScript + - JavaScript Reference + - Number + - Reference + - Référence(2) +translation_of: Web/JavaScript/Reference/Global_Objects/Number +--- +
{{JSRef}}
+ +

The Number JavaScript object is a wrapper object allowing you to work with numerical values. A Number object is created using the Number() constructor.

+ +

Constructor

+ +
new Number(value);
+ +

Parameters

+ +
+
value
+
The numeric value of the object being created.
+
+ +

Description

+ +

The primary uses for the Number object are:

+ + + +

Properties

+ +
+
{{jsxref("Number.EPSILON")}} {{experimental_inline}}
+
The smallest interval between two representable numbers.
+
{{jsxref("Number.MAX_SAFE_INTEGER")}} {{experimental_inline}}
+
The maximum safe integer in JavaScript (253 - 1).
+
{{jsxref("Number.MAX_VALUE")}}
+
The largest positive representable number.
+
{{jsxref("Number.MIN_SAFE_INTEGER")}} {{experimental_inline}}
+
The minimum safe integer in JavaScript (-(253 - 1)).
+
{{jsxref("Number.MIN_VALUE")}}
+
The smallest positive representable number - that is, the positive number closest to zero (without actually being zero).
+
{{jsxref("Number.NaN")}}
+
Special "not a number" value.
+
{{jsxref("Number.NEGATIVE_INFINITY")}}
+
Special value representing negative infinity; returned on overflow.
+
{{jsxref("Number.POSITIVE_INFINITY")}}
+
Special value representing infinity; returned on overflow.
+
{{jsxref("Number.prototype")}}
+
Allows the addition of properties to a Number object.
+
+ +
{{jsOverrides("Function", "properties", "MAX_VALUE", "MIN_VALUE", "NaN", "NEGATIVE_INFINITY", "POSITIVE_INFINITY", "protoype")}}
+ +

Methods

+ +
+
{{jsxref("Number.isNaN()")}} {{experimental_inline}}
+
Determine whether the passed value is NaN.
+
{{jsxref("Number.isFinite()")}} {{experimental_inline}}
+
Determine whether the passed value is a finite number.
+
{{jsxref("Number.isInteger()")}} {{experimental_inline}}
+
Determine whether the passed value is an integer.
+
{{jsxref("Number.isSafeInteger()")}} {{experimental_inline}}
+
Determine whether the passed value is a safe integer (number between -(253 - 1) and 253 - 1).
+
{{jsxref("Number.toInteger()")}} {{obsolete_inline}}
+
Used to evaluate the passed value and convert it to an integer (or {{jsxref("Global_Objects/Infinity", "Infinity")}}), but has been removed.
+
{{jsxref("Number.parseFloat()")}} {{experimental_inline}}
+
The value is the same as {{jsxref("Global_Objects/parseFloat", "parseFloat")}} of the global object.
+
{{jsxref("Number.parseInt()")}} {{experimental_inline}}
+
The value is the same as {{jsxref("Global_Objects/parseInt", "parseInt")}} of the global object.
+
+ +
{{jsOverrides("Function", "Methods", "isNaN")}}
+ +

Number instances

+ +

All Number instances inherit from {{jsxref("Number.prototype")}}. The prototype object of the Number constructor can be modified to affect all Number instances.

+ +

Methods

+ +
{{page('/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/prototype', 'Methods')}}
+ +

Examples

+ +

Example: Using the Number object to assign values to numeric variables

+ +

The following example uses the Number object's properties to assign values to several numeric variables:

+ +
var biggestNum = Number.MAX_VALUE;
+var smallestNum = Number.MIN_VALUE;
+var infiniteNum = Number.POSITIVE_INFINITY;
+var negInfiniteNum = Number.NEGATIVE_INFINITY;
+var notANum = Number.NaN;
+
+ +

Example: Integer range for Number

+ +

The following example shows minimum and maximum integer values that can be represented as Number object (for details, refer to EcmaScript standard, chapter 8.5 The Number Type):

+ +
var biggestInt = 9007199254740992;
+var smallestInt = -9007199254740992;
+
+ +

When parsing data that has been serialized to JSON, integer values falling out of this range can be expected to become corrupted when JSON parser coerces them to Number type. Using {{jsxref("Global_Objects/String", "String")}} instead is a possible workaround.

+ +

Example: Using Number to convert a Date object

+ +

The following example converts the {{jsxref("Global_Objects/Date", "Date")}} object to a numerical value using Number as a function:

+ +
var d = new Date('December 17, 1995 03:24:00');
+print(Number(d));
+
+ +

This displays "819199440000".

+ +

Example: Convert numeric strings to numbers

+ +
Number("123")     // 123
+Number("")        // 0
+Number("0x11")    // 17
+Number("0b11")    // 3
+Number("0o11")    // 9
+Number("foo")     // NaN
+Number("100a")    // NaN
+
+ +

Specifications

+ + + + + + + + + + + + + + + + + + + + + + + + +
SpecificationStatusComment
ECMAScript 1st Edition.StandardInitial definition. Implemented in JavaScript 1.1.
{{SpecName('ES5.1', '#sec-15.7', 'Number')}}{{Spec2('ES5.1')}} 
{{SpecName('ES6', '#sec-number-objects', 'Number')}}{{Spec2('ES6')}}New methods and properties added: ({{jsxref("Number.EPSILON", "EPSILON")}}, {{jsxref("Number.isFinite", "isFinite")}}, {{jsxref("Number.isInteger", "isInteger")}}, {{jsxref("Number.isNaN", "isNaN")}}, {{jsxref("Number.parseFloat", "parseFloat")}}, {{jsxref("Number.parseInt", "parseInt")}})
+ +

Browser compatibility

+ +
{{CompatibilityTable}}
+ +
+ + + + + + + + + + + + + + + + + + + +
FeatureChromeFirefox (Gecko)Internet ExplorerOperaSafari
Basic support{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}
+
+ +
+ + + + + + + + + + + + + + + + + + + + + +
FeatureAndroidChrome for AndroidFirefox Mobile (Gecko)IE MobileOpera MobileSafari Mobile
Basic support{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}
+
+ +

See also

+ + -- cgit v1.2.3-54-g00ecf