js-wrench/dist/modules/indexOf.js

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, ele, fromIndex) => {
    if (!isArray(data) && !isString(data))
        return -1;
    let len = data.length;
    if (len === 0)
        return -1;
    let index = fromIndex || 0;
    let i = Math.max(index >= 0 ? index : data.length - Math.abs(fromIndex), 0);
    while (i < len) {
        if (!isPrimitive(ele)) {
            const keys = isObj(ele) ? toKeys(ele) : ele;
            let sum = 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;