如何找到数组中的'abc‘[{title:'ccc'}，{title:'abc'}，{title:'ddd'，}]
如何找到数组中的'abc‘[{title:'ccc'}，{title:'abc'}，{title:'ddd'，}]
提问于 2019-06-10 17:00:14
我想知道{title:'ccc'}，{title: 'abc‘}，{title:'ddd'}中是否有’abc‘
let a = 'abc'
let b = [{title:'ccc'},{title:'abc'},{title:'ddd'}]if there is a in b{
return 'yes'
} else {
return 'no
}//怎么做，怎么判断
回答 6
Stack Overflow用户
回答已采纳
发布于 2019-06-10 17:05:00
最简单的答案是some
let a = 'abc'
let b = [{title:'ccc'},{title:'abc'},{title:'ddd'}];
let aInB = b.some(({ title }) => title == a);
console.log(aInB);
您还可以将includes与flatMap和Object.values一起使用
let a = 'abc'
let b = [{title:'ccc'},{title:'abc'},{title:'ddd'}];
let aInB = b.flatMap(Object.values).includes(a) ? "Yes" : "No";
console.log(aInB);
不含flatMap或flat的版本(不受良好支持)：
let a = 'abc'
let b = [{title:'ccc'},{title:'abc'},{title:'ddd'}];
let aInB = b.map(Object.values).reduce((a, c) => a.concat(c)).includes(a) ? "Yes" : "No";
console.log(aInB);
ES5语法：
var a = 'abc'
var b = [{title:'ccc'},{title:'abc'},{title:'ddd'}];
var aInB = b.map(function(e) {
return Object.keys(e).map(function(key) {
return e[key];
});
}).reduce(function(a, c) {
return a.concat(c);
}).indexOf(a) > -1 ? "Yes" : "No";
console.log(aInB);
Stack Overflow用户
发布于 2019-06-10 17:04:03
Array.prototype.some()
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/some
var a = 'abc';
var b = [
{value: 'def'},
{value: 'abc'},
{value: 'ghi'}
];
const result = b.some(x => x.value === a);
console.log(result);
Stack Overflow用户
发布于 2019-06-10 17:04:11
您可以使用Array#find。
如果没有找到匹配项，Array#find将返回匹配项或undefined，因此您可以在if语句中使用结果。
let a = 'abc'
let b = [{title:'ccc'},{title:'abc'},{title:'ddd'}]
let c = b.find((d) => d.title === a);
if (c) {
return 'yes';
} else {
return 'no';
}页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/56523338
复制相关文章
相似问题