# JS Lib ## Overview This class provides essential JavaScript constants and utility functions like Infinity, NaN, and undefined, along with URI encoding/decoding (encodeURI, decodeURIComponent) and string parsing (parseFloat, parseInt). It includes utilities like isFinite and isNaN for value validation and supports dynamic code evaluation through eval. ## **Returned Types** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md),[String](/reference/servoycore/dev-api/js-lib/string.md),[Date](/reference/servoycore/dev-api/js-lib/date.md),[Number](/reference/servoycore/dev-api/js-lib/number.md),[Array](/reference/servoycore/dev-api/js-lib/array.md),[Function](/reference/servoycore/dev-api/js-lib/function.md),[IterableValue](/reference/servoycore/dev-api/js-lib/iterablevalue.md),[Iterator](/reference/servoycore/dev-api/js-lib/iterator.md),[JSON](/reference/servoycore/dev-api/js-lib/json.md),[Map](/reference/servoycore/dev-api/js-lib/map.md),[Math](/reference/servoycore/dev-api/js-lib/math.md),[Namespace](/reference/servoycore/dev-api/js-lib/namespace.md),[QName](/reference/servoycore/dev-api/js-lib/qname.md),[RegExp](/reference/servoycore/dev-api/js-lib/regexp.md),[Set](/reference/servoycore/dev-api/js-lib/set.md),\[Special Operators]\(./special operators.md),[Statements](/reference/servoycore/dev-api/js-lib/statements.md),[XML](/reference/servoycore/dev-api/js-lib/xml.md),[XMLList](/reference/servoycore/dev-api/js-lib/xmllist.md),[BigInt](/reference/servoycore/dev-api/js-lib/bigint.md),[Promise](/reference/servoycore/dev-api/js-lib/promise.md), ## Properties Summarized | Type | Name | Summary | | -------------------------------------------------------- | ----------------------- | ------------------------------------ | | [Number](/reference/servoycore/dev-api/js-lib/number.md) | [Infinity](#infinity) | Numeric value representing infinity. | | [Number](/reference/servoycore/dev-api/js-lib/number.md) | [NaN](#nan) | Value representing Not-a-Number. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [undefined](#undefined) | The value undefined. | ## Methods Summarized | Type | Name | Summary | | ---------------------------------------------------------- | ---------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------ | | [String](/reference/servoycore/dev-api/js-lib/string.md) | [decodeURI(encodedURI)](#decodeuri-encodeduri) | Decodes a URI previously encoded with encodeURI or another similar routine. | | [String](/reference/servoycore/dev-api/js-lib/string.md) | [decodeURIComponent(encodedURI)](#decodeuricomponent-encodeduri) | Decodes a URI component previously created by encodeURIComponent or by a similar routine. | | [String](/reference/servoycore/dev-api/js-lib/string.md) | [encodeURI(URI)](#encodeuri-uri) | Encodes a URI by replacing certain characters with escape sequences. | | [String](/reference/servoycore/dev-api/js-lib/string.md) | [encodeURIComponent(URI)](#encodeuricomponent-uri) | Encodes a URI component by replacing all special characters with their corresponding UTF-8 escape sequences. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [eval(expression)](#eval-expression) | Evaluates JavaScript code passed as a string. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [isFinite(n)](#isfinite-n) | Returns true if the given number is a finite number. | | void | [isNaN(value)](#isnan-value) | The NaN property indicates that a value is 'Not a Number'. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [isXMLName(name)](#isxmlname-name) | Returns true if the given name can be used as a valid name for an XML element or attribute. | | [Number](/reference/servoycore/dev-api/js-lib/number.md) | [parseFloat(text)](#parsefloat-text) | Makes a floating point number from the starting numbers in a given string. | | [Number](/reference/servoycore/dev-api/js-lib/number.md) | [parseInt(text)](#parseint-text) | Makes a integer from the starting numbers in a given string in the base specified. | | [Number](/reference/servoycore/dev-api/js-lib/number.md) | [parseInt(text, radix)](#parseint-text-radix) | Makes a integer from the starting numbers in a given string in the base specified. | ## Properties Detailed ### Infinity Numeric value representing infinity. **Type**\ [Number](/reference/servoycore/dev-api/js-lib/number.md) **Sample** ```js Infinity ``` ### NaN Value representing Not-a-Number. **Type**\ [Number](/reference/servoycore/dev-api/js-lib/number.md) **Sample** ```js NaN ``` ### undefined The value undefined. **Type**\ [Object](/reference/servoycore/dev-api/js-lib/object.md) **Sample** ```js undefined ``` ## Methods Detailed ### decodeURI(encodedURI) Decodes a URI previously encoded with encodeURI or another similar routine. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **encodedURI** ; **Returns:** [String](/reference/servoycore/dev-api/js-lib/string.md) **Sample** ```js var str = "http://www.mysite.com/my code.asp?name=[cool]"; var encoded = encodeURI(str); var decoded = decodeURI(encoded); application.output(encoded);//http://www.mysite.com/my%20code.asp?name=%5bcool%5d application.output(decoded);//http://www.mysite.com/my code.asp?name=[cool] ``` ### decodeURIComponent(encodedURI) Decodes a URI component previously created by encodeURIComponent or by a similar routine. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **encodedURI** ; **Returns:** [String](/reference/servoycore/dev-api/js-lib/string.md) **Sample** ```js var str = "my code.asp?name=[cool]"; var encoded = encodeURIComponent(str); var decoded = decodeURIComponent(encoded); application.output(encoded); //my%20code.asp%3fname%3d%5bcool%5d application.output(decoded); //my code.asp?name=[cool] ``` ### encodeURI(URI) Encodes a URI by replacing certain characters with escape sequences. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **URI** ; **Returns:** [String](/reference/servoycore/dev-api/js-lib/string.md) **Sample** ```js var str = "http://www.mysite.com/my code.asp?name=[cool]"; var encoded = encodeURI(str); var decoded = decodeURI(encoded); application.output(encoded);//http://www.mysite.com/my%20code.asp?name=%5bcool%5d application.output(decoded);//http://www.mysite.com/my code.asp?name=[cool] ``` ### encodeURIComponent(URI) Encodes a URI component by replacing all special characters with their corresponding UTF-8 escape sequences. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **URI** ; **Returns:** [String](/reference/servoycore/dev-api/js-lib/string.md) **Sample** ```js var str = "my code.asp?name=[cool]"; var encoded = encodeURIComponent(str); var decoded = decodeURIComponent(encoded); application.output(encoded); //my%20code.asp%3fname%3d%5bcool%5d application.output(decoded); //my code.asp?name=[cool] ``` ### eval(expression) Evaluates JavaScript code passed as a string. Returns the value returned by the evaluated code. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **expression** ; **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) **Sample** ```js eval("var x = 2 + 3;"); application.output(x); // prints: 5.0 ``` ### isFinite(n) Returns true if the given number is a finite number. **Parameters** * [Number](/reference/servoycore/dev-api/js-lib/number.md) **n** ; **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) **Sample** ```js application.output(isFinite(1)); // prints: true application.output(isFinite(Infinity)); // prints: false application.output(isFinite(isNaN)); // prints: false ``` ### isNaN(value) The NaN property indicates that a value is 'Not a Number'. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **value** ; **Returns:** void **Sample** ```js isNaN( value ) ``` ### isXMLName(name) Returns true if the given name can be used as a valid name for an XML element or attribute.\ This was implemented by the Rhino engine as part of Ecma-357 which was meanwhile withdrawn. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **name** ; **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) **Sample** ```js application.output(isXMLName("good_name")); // prints: true application.output(isXMLName("bad name")); // because of the space, prints: false ``` ### parseFloat(text) Makes a floating point number from the starting numbers in a given string. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **text** ; **Returns:** [Number](/reference/servoycore/dev-api/js-lib/number.md) **Sample** ```js parseFloat('string') ``` ### parseInt(text) Makes a integer from the starting numbers in a given string in the base specified. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **text** ; **Returns:** [Number](/reference/servoycore/dev-api/js-lib/number.md) **Sample** ```js parseInt('0774') ``` ### parseInt(text, radix) Makes a integer from the starting numbers in a given string in the base specified. **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **text** ; * [Number](/reference/servoycore/dev-api/js-lib/number.md) **radix** ; **Returns:** [Number](/reference/servoycore/dev-api/js-lib/number.md) **Sample** ```js parseInt('0774' , 8) ``` *** --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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