Namespace: Util

Members

SuperMap.Util.DEFAULT_PRECISIONnumber

Valid digits reserved to avoid floating-point accuracy errors.

Default Value:

14

Methods

SuperMap.Util.applyDefaults(to, from){Object}

Util.js, line 234

Takes an object and copies any properties that don't exist from another properties, by analogy with SuperMap.Util.extend() from Prototype.js.

Name	Type	Description
to	Object	optional The destination object.
from	Object	The source object. Any properties of this object that are undefined in the to object will be set on the to object.

Returns:

Type	Description
Object	A reference to the to object. Note that the to argument is modified in place and returned by this function.

SuperMap.Util.calculateDpi(viewBounds, viewer, scale, coordUnit, datumAxis){number}

Util.js, line 739

Calculating the display resolution of the REST layer on the iServer service,Five parameters, viewBounds, viewer, scale, coordUnit, datumAxis, are required to be calculated from the REST layer representation of iServer.

Name	Type	Default	Description
viewBounds	SuperMap.Bounds		The reference visual range of a map, that is, the default map display range when the map is initialized.
viewer	SuperMap.Size		The size of the default map tile when the map is initialized.
scale	number		The default display scale when the map is initialized.
coordUnit	string	'degrees'	optional The map unit of the projection coordinate system.
datumAxis	number	6378137	optional Ellipsoid long half axis of the geo coordinate system. When user custom maps are Options, if the value of the parameter is not specified, the system is defaults to the ellipsoid long half axis 6378137 of the WGS84 reference system.

Returns:

Type	Description
number	Return the resolution of the layer display.

SuperMap.Util.cloneObject(obj){Object}

Util.js, line 963

Clone an object.

Name	Type	Description
obj	Object	An object that needs to be cloned.

Returns:

Type	Description
Object	To return to the object's copy object, note that it is a new object, not pointing to the object.

SuperMap.Util.copy(des, soc)

Util.js, line 62

Copy object.

Name	Type	Description
des	Object	optional Target object.
soc	Object	source object.

SuperMap.Util.copyAttributes(destination, source)

Util.js, line 911

copy attributes, don't copy method name(CLASS_NAME).

Name	Type	Description
destination	Object	optional The target object need to copy.
source	Object	The source object.

SuperMap.Util.copyAttributesWithClip(destination, source, clip)

Util.js, line 931

Copy attributes in the source object to the target object. （don't copy CLASS_NAME and function）

Name	Type	Description
destination	Object	optional the target object.
source	Object	the source object.
clip	Array.<string>	Properties that are forbidden to be copied to the target object in the source object. The purpose is to prevent the tampering of the non - modifiable attributes on the target object.

SuperMap.Util.createUniqueID(prefix){string}

Util.js, line 415

Create a unique ID value.

Name	Type	Description
prefix	string	optional prefix.

Returns:

Type	Description
string	The unique ID value.

SuperMap.Util.extend(destination, source){Object}

Util.js, line 25

Copy all properties of the source object to the target object. The undefined property that on the source object will not be set on the target object.

Name	Type	Description
destination	Object	optional Target object.
source	Object	source object. It's property will be set to the target object.

Returns:

Type	Description
Object	Target object.

Example

To copy all the properties of the SuperMap.Size object to the custom object, the use method is as follows:
    var size = new SuperMap.Size(100, 100);
    var obj = {}；
    SuperMap.Util.extend(obj, size);

SuperMap.Util.getBrowser(){Object}

Util.js, line 633

Get browser related information. Supported browsers include: Opera, Internet Explorer, Safari and Firefox.

Returns:

Type	Description
Object	Get the name, the version, and the device name of the browser. The corresponding attributes are name, version, device.

SuperMap.Util.getElement(){Array.<HTMLElement>}

Util.js, line 103

Get array of the HTML element.

Returns:

Type	Description
Array.<HTMLElement>	Array of the HTML element.

SuperMap.Util.getParameters(url){Object}

Util.js, line 354

Parsing the parameter objects from the URL string.

Name	Type	Description
url	string	URL。

Returns:

Type	Description
Object	Parsed parameter object.

SuperMap.Util.getParameterString(params){string}

Util.js, line 270

Transform the parameter object to the parameter string in the GEI request of HTTP. For example: "key1=value1&key2=value2&key3=value3"。

Name	Type	Description
params	Object	parameter object.

Returns:

Type	Description
string	The parameter string in the GEI request of HTTP.

SuperMap.Util.getResolutionFromScale(scale, units){number}

Util.js, line 547

Transform the scale to the resolution.

Name	Type	Default	Description
scale	number		The scale.
units	string	'degrees'	optional The unit of the scale.

Returns:

Type	Description
number	resolution.

SuperMap.Util.getResolutionFromScaleDpi(scale, dpi, coordUnit, datumAxis){number}

Util.js, line 846

Calculation the screen resolution according to scale and DPI.

Name	Type	Default	Description
scale	number		Scale.
dpi	number		Image resolution, representing the number of pixels per inch.
coordUnit	string		optional The map unit of the projection coordinate system.
datumAxis	number	6378137	optional Ellipsoid long half axis of the geo coordinate system. When user custom maps are Options, if the value of the parameter is not specified, the system is defaults to the ellipsoid long half axis 6378137 of the WGS84 reference system.

Returns:

Type	Description
number	Return to the current scale of screen resolution.

SuperMap.Util.getScaleFromResolution(resolution, units){number}

Util.js, line 566

Turn the scale into a resolution.

Name	Type	Default	Description
resolution	number		resolution.
units	string	'degrees'	optional The unit of the resolution.

Returns:

Type	Description
number	scale.

SuperMap.Util.getScaleFromResolutionDpi(resolution, dpi, coordUnit, datumAxis){number}

Util.js, line 874

Calculation of scale according to resolution, dpi, coordUnit and datumAxis.

Name	Type	Default	Description
resolution	number		Map resolution used to calculate scale.
dpi	number		Image resolution, representing the number of pixels per inch.
coordUnit	string		optional The map unit of the projection coordinate system.
datumAxis	number	6378137	optional Ellipsoid long half axis of the geo coordinate system. When user custom maps are Options, if the value of the parameter is not specified, the system is defaults to the ellipsoid long half axis 6378137 of the WGS84 reference system.

Returns:

Type	Description
number	Returns the scale of current screen resolution.

SuperMap.Util.getTextBounds(style, text, element){Object}

Util.js, line 1049

Get width and height of the text's outer rectangle.

Name	Type	Description
style	SuperMap.ThemeStyle	Text style.
text	string	text content.
element	Object	DOM element.

Returns:

Type	Description
Object	Return to the width and height information after cut.

SuperMap.Util.indexOf(array, obj){number}

Util.js, line 160

Get the index value of an object in an array.

Name	Type	Description
array	Array	array.
obj	Object	object.

Returns:

Type	Description
number	the index value of an object in an array.

SuperMap.Util.isArray(a){boolean}

Util.js, line 133

Determine whether an object is an array.

Name	Type	Description
a	Object	object.

Returns:

Type	Description
boolean	Whether it is an array.

SuperMap.Util.isElement(o){boolean}

Util.js, line 124

The "instance of" cross browser implementation.

Name	Type	Description
o	Object	object.

Returns:

Type	Description
boolean	Whether it is a page element.

SuperMap.Util.isInTheSameDomain(url){boolean}

Util.js, line 684

Determine whether a URL request is in the current domain.

Name	Type	Description
url	string	URL request string.

Returns:

Type	Description
boolean	whether a URL request is in the current domain.

SuperMap.Util.lineIntersection(a1, a2, b1, b2){Object}

Util.js, line 1004

Judge whether there is a intersection between the two lines.

Name	Type	Description
a1	SuperMap.Geometry.Point	The starting node of the first line segment.
a2	SuperMap.Geometry.Point	The end node of the first line segment.
b1	SuperMap.Geometry.Point	The starting node of the second line segment.
b2	SuperMap.Geometry.Point	The end node of the second line segment.

Returns:

Type	Description
Object	If the intersection returns to the intersection, if the disjoint is not intersected to return to the position relation of two line segments.

SuperMap.Util.modifyDOMElement(element, id, px, sz, position, border, overflow, opacity)

Util.js, line 190

Modify many of the attributes of a DOM element.

Name	Type	Description
element	HTMLElement	DOM elements to be modified.
id	string	optional ID of the DOM element.
px	SuperMap.Pixel	optional The left and top attributes that be contained on the style attribute of the DOM element.
sz	SuperMap.Size	optional The width and height attributes that be contained on the style attribute of the DOM element.
position	string	optional The position attribute of the DOM element.
border	string	optional The border attribute on the style of the DOM element.
overflow	string	optional The overflow attribute on the style of the DOM element.
opacity	number	optional Opacity value. The range of value is (0.0 - 1.0).

SuperMap.Util.normalizeScale(scale){number}

Util.js, line 536

Name	Type	Description
scale	number	scale

Returns:

Type	Description
number	Return to the normal scale value.

SuperMap.Util.rad(x){number}

Util.js, line 345

Transform degree to radian.

Name	Type	Description
x	number	The degree.

Returns:

Type	Description
number	The radian.

SuperMap.Util.removeItem(array, item){Array}

Util.js, line 144

Delete one item from the array.

Name	Type	Description
array	Array	array.
item	Object	An item that is to be deleted in an array.

Returns:

Type	Description
Array	The array after the execution of the delete operation.

SuperMap.Util.reset(obj)

Util.js, line 78

Disposes the resource. The property that references resource is set to null.

Name	Type	Description
obj	Object	optional Target object.

SuperMap.Util.supportCanvas(){boolean}

Util.js, line 666

Determine whether the browser supports Canvas.

Returns:

Type	Description
boolean	Whether the current browser supports HTML5 Canvas.

SuperMap.Util.toFloat(number, precision){number}

Util.js, line 329

The string is converted to a number with accuracy.

Name	Type	Default	Description
number	string		string.
precision	number	14	optional precision.

Returns:

Type	Description
number	Number.

SuperMap.Util.toJSON(obj){string}

Util.js, line 771

Transform the object to the JSON string.

Name	Type	Description
obj	Object	The object turned to the JSON.

Returns:

Type	Description
string	The JSON string.

SuperMap.Util.transformResult(result){Object}

Util.js, line 898

Transform the query result

Name	Type	Description
result	Object	the query result

Returns:

Type	Description
Object	The query results after the conversion.

SuperMap.Util.urlAppend(url, paramStr){string}

Util.js, line 305

Additional arguments to URL.

Name	Type	Description
url	string	URL strings to be added to parameters.
paramStr	string	The parameters to be added.

Returns:

Type	Description
string	The new URL.