我有一个包含重复项的数组。如何获得包含唯一项目的数组?
a= [{id: "1", campus: "c1"}, {id: "1", campus: "c1"}, {id: "2", campus: "c2"}, {id: "2", campus: "c2"}]
我想要带有唯一对象的结果
a= [{id: "1", campus: "c1"}, {id: "2", campus: "c2"}]
答案 0 :(得分:3)
您可以使用Array#filter
,如下所示:
var arr = [{
id: "1",
campus: "c1"
}, {
id: "1",
campus: "c1"
}, {
id: "2",
campus: "c2"
}, {
id: "2",
campus: "c2"
}];
// Keep an array of elements whose id is added in filtered array
var elementId = [];
var newArr = arr.filter(el => {
if (elementId.indexOf(el.id) === -1) {
// If not present in array, then add it
elementId.push(el.id);
return true;
} else {
// Already present in array, don't add it
return false;
}
});
console.log(newArr);
document.getElementById('result').innerHTML = JSON.stringify(newArr, 0, 4);
<pre id="result"></pre>
基于OP的comment
请提出有关表现的最佳方式..
如果您对下划线/ lodash
没问题您可以使用_.uniqWith
_.uniqWith(arr, _.isEqual);
var arr = [{
id: "1",
campus: "c1"
}, {
id: "1",
campus: "c1"
}, {
id: "2",
campus: "c2"
}, {
id: "2",
campus: "c2"
}];
var newArr = _.uniqWith(arr, _.isEqual);
console.log(newArr);
document.getElementById('result').innerHTML = JSON.stringify(newArr, 0, 4);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.0.1/lodash.js"></script>
<pre id="result"></pre>
您也可以使用_.uniqBy
_.uniqBy(arr, 'id');
var arr = [{
id: "1",
campus: "c1"
}, {
id: "1",
campus: "c1"
}, {
id: "2",
campus: "c2"
}, {
id: "2",
campus: "c2"
}];
var newArr = _.uniqBy(arr, 'id');
console.log(newArr);
document.getElementById('result').innerHTML = JSON.stringify(newArr, 0, 4);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.0.1/lodash.js"></script>
<pre id="result"></pre>
答案 1 :(得分:1)
Angular jqLite实现不包含$ .filter函数。
您必须提供自己的实施。你可以这样做:
function getUniqueArray(array){
var result = [];
for(var x = 0; x < array.length; x++){
if(result.indexOf(array[x]) == -1)
result.push(array[x]);
}
return result;
}
答案 2 :(得分:1)