54 lines
1.3 KiB
Markdown
54 lines
1.3 KiB
Markdown
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---
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title: Iterate Through All an Array's Items Using For Loops
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localeTitle: 使用for循环遍历所有数组的项目
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---
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## 使用for循环遍历所有数组的项目
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## 提示1
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* 必须使用嵌套的`for`循环来搜索数组中的每个元素。
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```javascript
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for (let i = 0; i < arr.length; i++) {
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```
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\`
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## 提示2
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* 然后必须将数组的每个元素与通过`filteredArray()`函数传递的`elem`参数进行比较。
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```javascript
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if (arr[i].indexOf(elem)==-1){
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```
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## 提示3
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* 如果未找到匹配，则`newArr`会添加整个子阵列。 `push()`函数在这里非常有用。
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```javascript
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newArr.push(arr[i]);
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```
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* 将整个子阵列添加到`newArr` ，循环继续下一个元素。
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## 解：
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```javascript
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function filteredArray(arr, elem) {
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let newArr = [];
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// change code below this line
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for (let i = 0; i < arr.length; i++) {
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if (arr[i].indexOf(elem)==-1){ //Checks every parameter for the element and if is NOT there continues the code
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newArr.push(arr[i]); //Inserts the element of the array in the new filtered array
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};
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};
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// change code above this line
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return newArr;
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};
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// change code here to test different cases:
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console.log(filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3));
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```
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