Dojo Learning notes 5. Dojo.lang.array & Dojo.lang.func & Dojo.string.extras

Module: Dojo.lang.array

Dojo.lang.has

To determine if an object has a specified property, but is this method useful, as a direct use of if (name in obj)

Usage Example:
　dojo.lang.has(dojo.lang, "has");　//will return true
dojo.lang.isEmpty

To determine whether an object or array is empty

Usage Example:
　dojo.lang.isEmpty({a: 1});　//will return false
　dojo.lang.isEmpty([]);　//will return true
dojo.lang.map

Invokes the specified method to handle the specified array or string

Usage Example:
　dojo.lang.map([1,2,3,4,5], function(x) { return x * x;});　//will return [1,4,9,16,25]
dojo.lang.forEach

Iterates through the specified array or string and invokes the specified method on the element

Usage Example:
　dojo.lang.forEach("abc", function(x) { alert(x); });
dojo.lang.every

Checks whether the specified array satisfies the criteria for the specified method

Usage Example:

Dojo.lang.every ([1,-2,3], function (x) {return x > 0;}); The specified array is not all greater than 0, so returns false

Dojo.lang.some

Checks whether the specified array partially meets the criteria for the specified method

Usage Example:
　dojo.lang.some([1,-2,3], function(x) { return x > 0; });　//指定的数组有大于0的元素，因此返回true
dojo.lang.filter

Filters the specified array according to the specified method

Usage Example:
　dojo.lang.filter([1,-2,3], function(x) { return x > 0; });　//will return [1, 3]
dojo.lang.unnest

Converts the specified argument or array to a one-dimensional array

Usage Example:
　dojo.lang.unnest(1, 2, 3);　//will return [1, 2, 3]
　dojo.lang.unnest(1, [2, [3], [{4}]]);　//will return [1, 2, 3, 4]

Dojo.lang.toArray

Convert input to an array

Usage Example:
　function test()
　{
　　return dojo.lang.toArray(arguments, 1);
　}
　test(1,2,3,4,5);　//will return [2,3,4,5]

Module: Dojo.lang.func

Dojo.lang.hitch

Hangs the specified method under the specified object and returns the method

Usage Example:
　func = {test: function(s) {alert(s)}};
　dojo.lang.mixin(func, {demo: dojo.lang.hitch(func, "test")});
　func.demo("demo and test are same method");
dojo.lang.forward

Returns a method reference for the specified name of its own object

Usage Example:
　func = {test: function(s) {alert(s)}, demo: dojo.lang.forward("test")};
　func.demo("demo and test are same method");
dojo.lang.curry
What is curry? 请参阅这篇文章：http://www.svendtofte.com/code/curried_javascript/
Usage Example:
　function add(a, b)
　{
　　return a + b;
　}
　dojo.lang.curry(null, add, 2, 3);　//will return 5
　dojo.lang.curry(null, add, 2)(3);　//will return 5
　dojo.lang.curry(null, add)(2)(3);　//will return 5
　dojo.lang.curry(null, add)()(2)(3);　//will return 5
dojo.lang.curryArguments

Similar to Dojo.lang.curry, but you can choose to ignore the first n parameters

Usage Example:
　function add(a, b)
　{
　　return a + b;
　}
　dojo.lang.curryArguments(null, add, [1,2,3,4,5], 2);　//will return 5 (= 2 + 3)
　
dojo.lang.tryThese