Javascript: array.indexOf() 没有返回正确的元素索引
Javascript: array.indexOf() not returning correct index of elements
数组:
values: [5,4,4,5,6,6]
我想获取元素的索引。所以,我正在遍历它。
values.map((val) => {
console.log('val', value.indexOf(val));
console.log('val of 5', value.indexOf(5));
console.log('val of 4', value.indexOf(4));
console.log('val of 4', value.indexOf(4));
console.log('val of 5', value.indexOf(5));
console.log('val of 6', value.indexOf(6));
console.log('val of 6', value.indexOf(6));
return value.indexOf(val);
});
expected output
0,1,2,3,4
当前输出
0
1
1
0
4
4
我哪里错了?
const values = [5,4,4,5,6,6]
const indexes = values.map((val, idx) => {
console.log(`Index of ${val} is ${idx}`);
return idx;
});
数组:
values: [5,4,4,5,6,6]
我想获取元素的索引。所以,我正在遍历它。
values.map((val) => {
console.log('val', value.indexOf(val));
console.log('val of 5', value.indexOf(5));
console.log('val of 4', value.indexOf(4));
console.log('val of 4', value.indexOf(4));
console.log('val of 5', value.indexOf(5));
console.log('val of 6', value.indexOf(6));
console.log('val of 6', value.indexOf(6));
return value.indexOf(val);
});
expected output
0,1,2,3,4
当前输出
0
1
1
0
4
4
我哪里错了?
const values = [5,4,4,5,6,6]
const indexes = values.map((val, idx) => {
console.log(`Index of ${val} is ${idx}`);
return idx;
});