字串首字母轉化為大寫

/**
 * 字串首字母轉化為大寫 ios_bbbbbbbb -> iosBbbbbbbbb
 */
func strFirstToUpper(str string) string {
    temp := strings.Split(str, "_")
    var upperStr string
    for y := 0; y < len(temp); y++ {
        vv := []rune(temp[y])
        if y != 0 {
            for i := 0; i < len(vv); i++ {
                if
 
 i == 0 {
                    vv[i] -= 32
                    upperStr += string(vv[i]) // + string(vv[i+1])
                } else {
                    upperStr += string(vv[i])
                }
            }
        }
    }
    return temp[0] + upperStr
}