面试题一道

const testData = {
    a_bbb: 123,
    a_g: [1, 2, 3, 4],
    a_d: {
        s: 2,
        s_d: 3
    },
    a_f: [1, 2, 3, {
        a_g: 5
    }],
    a_d_s: 1
}

/**
 * _w 的形式转成 W
 */
function toCame(str) {
    return str.replace(/\_(\w)/g, function(a, b) {
        return b.toUpperCase();
    });
}

/**
 * 将一个json数据的所有key从下划线改为驼峰
 * 
 * @param {object | array} value 待处理对象或数组
 * @returns {object | array} 处理后的对象或数组
 */
function mapKeysToCamelCase(data) {
    if(data instanceof Array) {
        data.forEach(function(v, index) {
            mapKeysToCamelCase(v);
        });
    } else if(data instanceof Object) {
        Object.keys(data).forEach(function(v, index) {
            var newValue = toCame(v);
            console.info(newValue);
            
            // 如果名称一致，说明可能不存在转化情况
            if(newValue != v) {
                data[newValue] = data[v];
                delete data[v];
            }

            // 递归
            mapKeysToCamelCase(data[newValue]);
        });
    }

    return data;
}

console.log(mapKeysToCamelCase(testData))