最好的转换方式是什么:
['a','b','c']
to:
{
0: 'a',
1: 'b',
2: 'c'
}
最好的转换方式是什么:
['a','b','c']
to:
{
0: 'a',
1: 'b',
2: 'c'
}
当前回答
更多的浏览器支持和更灵活的方法是使用一个正常的循环,比如:
const arr = ['a', 'b', 'c'],
obj = {};
for (let i=0; i<arr.length; i++) {
obj[i] = arr[i];
}
但现代的方法也可以使用展开运算符,比如:
{...arr}
或对象赋值:
Object.assign({}, ['a', 'b', 'c']);
两者都会返回:
{0: "a", 1: "b", 2: "c"}
其他回答
打印稿solutioin:
export const toMap = (errors: ResponseError[]) => {
const errorMap: Record<string, string> = {};
errors.forEach(({ field, message }) => {
errorMap[field] = message;
});
return errorMap;
};
export type FieldError = {
field: string;
message: string;
};
这是我刚刚写的递归函数。这很简单,而且效果很好。
// Convert array to object
var convArrToObj = function(array){
var thisEleObj = new Object();
if(typeof array == "object"){
for(var i in array){
var thisEle = convArrToObj(array[i]);
thisEleObj[i] = thisEle;
}
}else {
thisEleObj = array;
}
return thisEleObj;
}
下面是一个例子(jsFiddle):
var array = new Array();
array.a = 123;
array.b = 234;
array.c = 345;
var array2 = new Array();
array2.a = 321;
array2.b = 432;
array2.c = 543;
var array3 = new Array();
array3.a = 132;
array3.b = 243;
array3.c = 354;
var array4 = new Array();
array4.a = 312;
array4.b = 423;
array4.c = 534;
var array5 = new Array();
array5.a = 112;
array5.b = 223;
array5.c = 334;
array.d = array2;
array4.d = array5;
array3.d = array4;
array.e = array3;
console.log(array);
// Convert array to object
var convArrToObj = function(array){
var thisEleObj = new Object();
if(typeof array == "object"){
for(var i in array){
var thisEle = convArrToObj(array[i]);
thisEleObj[i] = thisEle;
}
}else {
thisEleObj = array;
}
return thisEleObj;
}
console.log(convArrToObj(array));
结果:
如果有人在搜索Typescript方法,我这样写:
const arrayToObject = <T extends Record<K, any>, K extends keyof any>(
array: T[] = [],
getKey: (item: T) => K,
) =>
array.reduce((obj, cur) => {
const key = getKey(cur)
return ({...obj, [key]: cur})
}, {} as Record<K, T>)
它将:
强制第一个参数为对象数组 帮助选择键 强制该键为所有数组项的键
例子:
// from:
const array = [
{ sid: 123, name: 'aaa', extra: 1 },
{ sid: 456, name: 'bbb' },
{ sid: 789, name: 'ccc' }
];
// to:
{
'123': { sid: 123, name: 'aaa' },
'456': { sid: 456, name: 'bbb' },
'789': { sid: 789, name: 'ccc' }
}
用法:
const obj = arrayToObject(array, item => item.sid) // ok
const obj = arrayToObject(array, item => item.extra) // error
这是一个演示。
如果你正在使用jquery:
$.extend({}, ['a', 'b', 'c']);
如果数组包含2元素数组,其中第一个元素是键,第二个元素是值,您可以使用reduce轻松地将其转换为对象。
[
["key1","value1"],
["key2", "value2"],
["key3", "value3"]
]
.reduce((acc, [key, value])=>({...acc, [key]: value}), {});
结果:
{
key1: 'value1',
key2: 'value2',
key3: 'value3'
}