// 下划线转换驼峰

function toHump(name) {

    return name.replace(/\_(\w)/g, function(all, letter){

        return letter.toUpperCase();

    });

}

// 驼峰转换下划线

function toLine(name) {

  return name.replace(/([A-Z])/g,"_$1").toLowerCase();

}

// 测试

let a = 'a_b2_345_c2345';

console.log(toHump(a));

let b = 'aBdaNf';

console.log(toLine(b));