Servoy 2020 Documentation
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Refresh page Mar 22, 2023 05:05

Supported Clients
SmartClient WebClient NGClient MobileClient

Property Summary
Function constructor Specifies the function that creates an object's prototype.
Number length Specifies the number of arguments expected by the function.

Methods Summary
void apply() Applies the method of another object in the context of a different object (the calling object); arguments can be passed as an Array object.
void bind() Creates a new function which, when called, itself calls this function in the context of the provided value, with a given sequence of arguments preceding any provided when the new function was called.
void call() Calls (executes) a method of another object in the context of a different object (the calling object); arguments can be passed as they are.
String toString() Returns a string representing the source code of the function.

Property Details

constructor

 
Specifies the function that creates an object's prototype.

Returns

Function

Supported Clients

SmartClient,WebClient,NGClient,MobileClient

Sample

function Tree(name) {
	this.name = name;
}
theTree = new Tree("Redwood");
console.log("theTree.constructor is " + theTree.constructor);

length

 
Specifies the number of arguments expected by the function.

Returns

Number

Supported Clients

SmartClient,WebClient,NGClient,MobileClient

Sample

function addNumbers(x, y){
	if (addNumbers.length == 2) {
		return (x + y);
	} else
		return 0;
}

Methods Details

apply()

 
Applies the method of another object in the context of a different object (the calling object); arguments can be passed as an Array object.

Supported Clients

SmartClient,WebClient,NGClient,MobileClient

Sample

function book(name, author) {
	this.name = name;
	this.author = author;
}

function book_with_topic(name, author, topic) {
	this.topic = topic;
	book.apply(this, arguments);
}
book_with_topic.prototype = new book();

var aBook = new book_with_topic("name","author","topic");

bind()

 
Creates a new function which, when called, itself calls this function in the context of the provided value, with a given sequence of arguments preceding any provided when the new function was called.

Supported Clients

SmartClient,WebClient,NGClient,MobileClient

Sample

var x = 9, 
	module = {
		getX: function() { 
		     return this.x;
		},
		x: 81
	};
//  "module.getX()" called, "module" is "this", "module.x" is returned
module.getX(); // > 81
//  "getX()" called, "this" is global, "x" is returned
getX(); // > 9
//  store a reference with "module" bound as "this"
var boundGetX = getX.bind(module);
//  "boundGetX()" called, "module" is "this" again, "module.x" is returned
boundGetX(); // > 81

call()

 
Calls (executes) a method of another object in the context of a different object (the calling object); arguments can be passed as they are.

Supported Clients

SmartClient,WebClient,NGClient,MobileClient

Sample

function book(name) {
	this.name = name;
}

function book_with_author(name, author) {
	this.author = author;
	book.call(this, name);
}
book_with_author.prototype = new book();

var aBook = new book_with_author("name","author");

toString()

 
Returns a string representing the source code of the function. Overrides the Object.toString method.

Returns

String

Supported Clients

SmartClient,WebClient,NGClient,MobileClient

Sample

function printHello() {
	return "Hello";
}
application.output(printHello.toString());

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