L.Util

Util

Various utility functions, used by Leaflet internally.

Methods

Method	Returns	Description
`extend( <Object> dest, <Object> src?.. )`	`Object`	Merges the properties of the `src` object (or multiple objects) into `dest` object and returns the latter. Has an `L.extend` shortcut.
`bind( <Function> fn, <Object> obj )`	`Function`	Returns a function which executes function `fn` with the given scope `obj` (so that `this` keyword refers to `obj` inside the function code). Has an `L.bind` shortcut. Not a polyfill for ES 5 `bind` (compare `L.bind` to the MDN-recommended polyfill for `Function.prototype.bind`).
`stamp( <Object> obj )`	`String`	Applies a unique key to the object and returns that key. Has an `L.stamp` shortcut.
`requestAnimFrame( <Function> fn, <Object> context?, <Boolean> immediate?, <HTMLElement> element? )`	`Number`	Schedules `fn` to be executed when the browser repaints. When `immediate` is set, `fn` is called immediately if the browser doesn't have native support for `requestAnimationFrame`, otherwise it's delayed. Returns an id that can be used to cancel the request.
`cancelAnimFrame( <Number> id )`	-	Cancels a previous request to `requestAnimFrame`.
`limitExecByInterval( <Function> fn, <Number> time, <Object> context? )`	`Function`	Returns a wrapper around the function `fn` that makes sure it's called not more often than a certain time interval `time`, but as fast as possible otherwise (for example, it is used for checking and requesting new tiles while dragging the map), optionally passing the scope (`context`) in which the function will be called.
`falseFn()`	`Function`	Always returns `false`.
`formatNum( <Number> num, <Number> digits )`	`Number`	Returns the number `num` rounded to `digits` decimals.
`splitWords( <String> str )`	`String[]`	Trims and splits the string on whitespace and returns the array of parts.
`setOptions( <Object> obj, <Object> options )`	`Object`	Merges the given properties to the `options` of the `obj` object, returning the resulting options. See Class options. Has an `L.setOptions` shortcut.
`getParamString( <Object> obj )`	`String`	Converts an object into a parameter URL string, e.g. `{a: "foo", b: "bar"}` translates to `'?a=foo&b=bar'`.
`template( <String> str, <Object> data )`	`String`	Simple templating facility, accepts a template string of the form `'Hello {a}, {b}'` and a data object like `{a: 'foo', b: 'bar'}`, returns evaluated string (`'Hello foo, bar'`). You can also specify functions instead of strings for data values — they will be evaluated passing `data` as an argument.
`isArray( <Object> obj )`	`Boolean`	Returns `true` if the given object is an array.
`trim( <String> str )`	`String`	Trims the whitespace from both ends of the string and returns the result.

Properties

Property	Type	Description
`emptyImageUrl`	`String`	Data URI string containing a base64-encoded empty GIF image. Used as a hack to free memory from unused images on WebKit-powered mobile devices (by setting image `src` to this string).