has
dojo/has
Summary
Return the current value of the named feature.
Returns the value of the feature named by name. The feature must have been previously added to the cache by has.add.
Usage
Parameter | Type | Description |
---|---|---|
name | String | Integer |
The name (if a string) or identifier (if an integer) of the feature to test. |
Returns: boolean
See the dojo/has reference documentation for more information.
Properties
cache
Defined by: dojo/has
Methods
add(name,test,now,force)
Defined by dojo/has
Register a new feature test for some named feature.
Parameter | Type | Description |
---|---|---|
name | String | Integer |
The name (if a string) or identifier (if an integer) of the feature to test. |
test | Function |
A test function to register. If a function, queued for testing until actually needed. The test function should return a boolean indicating the presence of a feature or bug. |
now | Boolean | Optional
Optional. Omit if |
force | Boolean | Optional
Optional. If the test already exists and force is truthy, then the existing test will be replaced; otherwise, add does not replace an existing test (that is, by default, the first test advice wins). |
Returns: undefined
Examples
Example 1
A redundant test, testFn with immediate execution:
has.add("javascript", function(){ return true; }, true);
Example 2
Again with the redundantness. You can do this in your tests, but we should not be doing this in any internal has.js tests
has.add("javascript", true);
Example 3
Three things are passed to the testFunction. global
, document
, and a generic element from which to work your test should the need arise.
has.add("bug-byid", function(g, d, el){
// g == global, typically window, yadda yadda
// d == document object
// el == the generic element. a `has` element.
return false; // fake test, byid-when-form-has-name-matching-an-id is slightly longer
});
clearElement(element)
Defined by dojo/has
Deletes the contents of the element passed to test functions.
Parameter | Type | Description |
---|---|---|
element | undefined |
load(id,parentRequire,loaded)
Defined by dojo/has
Conditional loading of AMD modules based on a has feature test value.
Parameter | Type | Description |
---|---|---|
id | String |
Gives the resolved module id to load. |
parentRequire | Function |
The loader require function with respect to the module that contained the plugin resource in it's dependency list. |
loaded | Function |
Callback to loader that consumes result of plugin demand. |
normalize(id,toAbsMid)
Defined by dojo/has
Resolves id into a module id based on possibly-nested tenary expression that branches on has feature test value(s).
Parameter | Type | Description |
---|---|---|
id | undefined | |
toAbsMid | Function |
Resolves a relative module id into an absolute module id |
© 2005–2015 The Dojo Foundation
Licensed under the AFL 2.1 and BSD 3-Clause licenses.
http://dojotoolkit.org/api/1.10/dojo/has.html