dojo 官方翻译 dojo/_base/array 版本1.10

官方地址：http://dojotoolkit.org/reference-guide/1.10/dojo/_base/array.html#dojo-base-array

array模块dojo进行了很好的封装，如果想要调用必须先加载该模块：

require(["dojo/_base/array"], function(array){
  // array contains the features
});

　　indexOf()

返回值：字符串在数组中第一次出现的位置，如果没有找到默认返回-1.

require(["dojo/_base/array"], function(array){
  array.indexOf(arrayObject, valueToFind, fromIndex, findLast);
});

　　示例：

require(["dojo/_base/array", "dojo/dom", "dojo/dom-construct", "dojo/on", "dojo/domReady!"],
function(array, dom, domConst, on){

  var arrIndxOf = ["foo", "hoo", "zoo"];

  on(dom.byId("refButton1"), "click", function(){
    var position = array.indexOf(arrIndxOf, "zoo");
    domConst.place(
      "<p>The index of the word 'zoo' within the array is " + position + "</p>",
      "result1",
      "after"
    );
  });

});
<div>The content of our test array is <code>["foo", "hoo", "zoo"]</code>.</div>
<button id="refButton1" type="button">Show the index of the word 'zoo' within the array.</button>
<div id="result1"></div>

lastIndexOf()

返回值：字符串在数组中的最后位置，如果没有找到默认返回-1.

require(["dojo/_base/array"], function(array){
  array.lastIndexOf(arrayObject, valueToFind, fromIndex);
});

示例：

require(["dojo/_base/array", "dojo/dom-construct", "dojo/dom", "dojo/on", "dojo/domReady!"],
function(array, domConst, dom, on){

  var arrLastIndxOf = ["foo", "hoo", "zoo", "shoe", "zoo", "nuu"];

  on(dom.byId("refButton2"), "click", function(){
    var position = array.lastIndexOf(arrLastIndxOf, "zoo");
    domConst.place(
      "<p>The last index of the word 'zoo' within the array is " + position + "</p>",
      "result2",
      "after"
    );
  });
});
<div>The content of our test array is <code>["foo", "hoo", "zoo", "shoe", "zoo", "nuu"]</code>.</div>
<button id="refButton2" type="button">Show the last index of the word 'zoo' within the array.</button>
<div id="result2"></div>

forEach()

遍历数组或者nodelists。

require(["dojo/_base/array"], function(array){
  array.forEach(arrayObject, callback, thisObject);
});

第三个参数，调节forEach（）的访问范围。

示例：

require(["dojo/_base/array"], function(array){
  var foo = {
    myMethod: function(el){
        console.log(el);
    }
  };

  array.forEach(["a","b","c"],function(item){
    this.myMethod(item);
  }, foo);
});

如果你想break这个循环，可以使用some（）

require(["dojo/_base/array", "dojo/dom", "dojo/on", "dojo/domReady!"],
function(array, dom, on){

  on(dom.byId("start"), "click", function(){
    var myArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
        count;

    // iterate ALL entries of myArray
    count = 0;
    array.forEach(myArray, function(entry){
      count++;
    });

    alert("iterated " + count + " entries (forEach())"); // will show "iterated 10 entries"

    // let's only iterate the first 4 entries of myArray
    count = 0;
    array.some(myArray, function(entry){
      if(count >= 4){
        return false;
      }
      count++;
    });

    alert("iterated "+count+" entries (some())"); // will show "iterated 4 entries"
  });
});
<button id="start" type="button">Start Testloops</button>

filter()

返回值：数组过滤之后的结果数组。

require(["dojo/_base/array"], function(array){
  filteredArray = array.filter(unfilteredArray, callback, thisObject);
});

示例：

require(["dojo/_base/array", "dojo/dom", "dojo/dom-construct", "dojo/on", "dojo/domReady!"],
function(array, dom, domConst, on){
  var arr = [
    { surname: "Washington", name: "Paul" },
    { surname: "Gordon", name: "Amie" },
    { surname: "Meyer", name: "Sofie" },
    { surname: "Jaysons", name: "Josh" },
    { surname: "Washington", name: "George" },
    { surname: "Doormat", name: "Amber" },
    { surname: "Smith", name: "Susan" },
    { surname: "Hill", name: "Strawberry" },
    { surname: "Washington", name: "Dan" },
    { surname: "Dojo", name: "Master" }
  ];

  on(dom.byId("start"), "click", function(){
    var filteredArr = array.filter(arr, function(item){
      return item.surname == "Washington";
    });

    array.forEach(filteredArr, function(item, i){
      domConst.create("li", {innerHTML: i+1+". "+item.surname+", "+item.name}, "filtered-items");
    });

    array.forEach(arr, function(item, i){
      domConst.create("li", {innerHTML: i+1+". "+item.surname+", "+item.name}, "unFiltered-items");
    });
  });
});
<button id="start" type="button">Filter array</button>
<br/>
<div style="width: 300px; float: left;">
  Filtered items<br />
  (only people with "Washington" as surname)
  <ul id="filtered-items">

  </ul>
</div>
<div style="width: 300px; float: left;">
  Unfiltered items<br />
  (all people are represented in the list)
  <ul id="unFiltered-items">

  </ul>
</div>

map()

返回值：经过修改之后的另外一个数组。

require(["dojo/_base/array"], function(array){
  array.map(arrayObject, callback, thisObject);
});

示例：

require(["dojo/_base/array", "dojo/dom", "dojo/dom-construct", "dojo/on", "dojo/domReady!"],
function(array, dom, domConst, on){

  var arrValues = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

  on(dom.byId("button"), "click", function(){
    var doubleValue = array.map(arrValues, function(item){
      return item * 2;
    });

    array.forEach(doubleValue, function(item){
      var li = domConst.create("li");
      li.innerHTML = item;
      dom.byId("arrValuesAfter-items").appendChild(li);
    });

    array.forEach(arrValues, function(item){
      var li = domConst.create("li");
      li.innerHTML = item;
      dom.byId("arrValues-items").appendChild(li);
    });
  });
});
<button id="button" type="button">Run array.map()</button>
<br />
<div style="width: 300px; float: left; margin-top: 10px;">
  Values before running array.map()
  <ul id="arrValues-items"></ul>
</div>
<div style="width: 300px; float: left; margin-top: 10px;">
  Values after running array.map()
  <ul id="arrValuesAfter-items"></ul>
</div>

有时候为了不修改原数组本身，dojo提供了dojo/_base/lang::clone()

示例：

require(["dojo/_base/array", "dojo/_base/lang", "dojo/dom", "dojo/dom-construct", "dojo/on", "dojo/domReady!"],
function(array, lang, dom, domConst, on){

  var arrSalary = [
    { surname: "Washington", name: "Paul", salary: 200 },
    { surname: "Gordon", name: "Amie", salary: 350 },
    { surname: "Meyer", name: "Sofie", salary: 100 },
    { surname: "Jaysons", name: "Josh", salary: 2500 },
    { surname: "Washington", name: "George", salary: 10 },
    { surname: "Doormat", name: "Amber", salary: 320 },
    { surname: "Smith", name: "Susan", salary: 3200 },
    { surname: "Hill", name: "Strawberry", salary: 290 },
    { surname: "Washington", name: "Dan", salary: 200 },
    { surname: "Dojo", name: "Master", salary: 205 }
  ];

  on(dom.byId("button"), "click", function(){
    var raisedSalaries = array.map(arrSalary, function(item){
      var newItem = lang.clone(item);
      newItem.salary += (newItem.salary/100)*10;
      return newItem;
    });

    array.forEach(raisedSalaries, function(item, i){
      var li = domConst.create("li");
      li.innerHTML = i+1+". "+item.surname+", "+item.name+". New salary: "+item.salary;
      dom.byId("filteredSalary-items").appendChild(li);
    });

    array.forEach(arrSalary, function(item, i){
      var li = domConst.create("li");
      li.innerHTML = i+1+". "+item.surname+", "+item.name+". Old salary: "+item.salary;
      dom.byId("unFilteredSalary-items").appendChild(li);
    });
  });
});
<button id="button" type="button">Raise the salary</button>
<br />
<div style="width: 300px; float: left; margin-top: 10px;">
  Peoples' salaries after raise:
  <ul id="filteredSalary-items"></ul>
</div>
<div style="width: 300px; float: left; margin-top: 10px;">
  Peoples' salaries before raise:
  <ul id="unFilteredSalary-items"></ul>
</div>

some()

返回值：true or  false。只要方法里有一个是真，那么其将会返回true。常常被用在if语句中。

require(["dojo/_base/array"], function(array){
  var a = array.some(arrayObject, callback, thisObject);
});

示例：检查是否有一个值 >= 1,000,000。

require(["dojo/_base/array", "dojo/dom", "dojo/dom-construct", "dojo/on", "dojo/domReady!"],
function(array, dom, domConst, on){
  var arrIndxSome = [200000, 500000, 350000, 1000000, 75, 3];

  on(dom.byId("refButton6"), "click", function(){
    if(array.some(arrIndxSome, function(item){ return item >= 1000000; })){
      result = 'yes, there are';
    }else{
      result = 'no, there are no such items';
    }

    domConst.place(
      "<p>The answer is: " + result + "</p>",
      "result6",
      "after"
    );
  });
});
<div>The content of our test array is <code>[200000, 500000, 350000, 1000000, 75, 3]</code>.</div>
<button id="refButton6" type="button">Are there some items >=1000000 within the array?</button>
<div id="result6"></div>

every()

返回值：true or false  。只有当方法里面，每一项都返回true，那么最终才会返回true。常常被用在if语句中。

require(["dojo/_base/array"], function(array){
  array.every(arrayObject, callback, thisObject);
});

示例：检查是否每一项都>3000

require(["dojo/_base/array", "dojo/dom", "dojo/dom-construct", "dojo/on", "dojo/domReady!"],
function(array, dom, domConst, on){

  var arrIndxEvery = [
    { month: "january", income: 2000 },
    { month: "february", income: 3200 },
    { month: "march", income: 2100 }
  ];

  on(dom.byId("refButton7"), "click", function(){
    if(array.every(arrIndxEvery , function(item){ return item.income >= 3000; })){
      result = "yes, all income >= 3000";
    }else{
      result = "no, not all income >= 3000";
    }
    domConst.place(
      "<p>The answer is: " + result + "</p>",
      "result7",
      "after"
    );
  });
});
<div>The content of our test array is <code>[{ month: "january", income: 2000 }, { month: "february", income: 3200 }, { month: "march", income: 2100 }]</code>.</div>
<button id="refButton7" type="button">Is the client allowed to get the credit?</button>
<div id="result7"></div>