js-wrench/modules/indexOf.ts

JS函数库

import isArray from './isArray'
import isString from './isString'
import isObj from './isObj';
import toKeys from './toKeys';
import has from './has';
import isPrimitive from './isPrimitive';
/**
 * @description indexOf 从头到尾地检索 如果有返回索引值
 *
 * @param {(any[] | string)} data 需要查找的数组或者字符串
 * @param {any} ele 指定的值, 可以是数字,字符串,对象
 * @param {(number | undefined)} [fromIndex] 从指定位置开始查找 可选
 * @return {*}  {number} 返回第一次出现的索引, 如果没有找到, 则返回-1
 * @example indexOf([1,2,3], 1) => 0 indexOf([{c:1}, {a:1,b:2}], {a:1}) => -1 indexOf([[1], [2,3]], [2,3]) => 1
 */
const indexOf = (
	data: any[] | string,
	ele: any,
	fromIndex?: number
): number => {
	if(!isArray(data) && !isString(data)) return -1;
	let len: number = data.length
	if (len === 0) return -1
	let index: number = fromIndex || 0
	let i: number = Math.max(
		index >= 0 ? index : data.length - Math.abs(fromIndex as number),
		0
	)
	while (i < len) {
		if(!isPrimitive(ele)) {
			const keys:any[] = isObj(ele) ? toKeys(ele) : ele
			let sum:number = 0;
			for(let key in ele) {
				if(has(data[i], key) && data[i][key] === ele[key]) {
					sum++		//用计数的方式判断
				}
			}
			if(sum === keys.length) return i;
		}else {
			if (data[i] === ele) return i
		}
		i++
	}
	return -1
}
export default indexOf