Question

我有很多这样的字符串：

NewImage": {
  "likes": {
    "N": "5"
  },
  "is_em": {
    "B": "ZWFzdXJlLg=="
  },
  "id": {
    "N": "9"
  },
  "user_access_key_id": {
    "S": "ASIAJIGCYGKAOSMJN6MA"
  }
}

我想将它们转换为具有以下特征的句子：

小写
＆＃34;和＆＃34;分离倒数第二个和最后一个元素
否则＆＃34;，＆＃34;分离每个元素
如果只有2个元素，那么它们应该打印为＆＃34; xx和xx＆＃34;
如果只有1个元素，则应打印为＆＃34; xx＆＃34;

所以这些字符串上面的字符串应该像这样打印：

x1 <- c("Red", "Green", "Blue")
x2 <- c("Red", "Green", "Orange", "Yellow", "Pink")
x3 <- c("Red", "Green")
x4 <- c("Red")
x5 <- c("Red", "Green", "Orange", "Yellow", "Pink", "Blue", "Green")

我开始做一个功能来实现上述目标，这是我得到了多远：

# red, green and blue
# red, green, orange, yellow and pink
# red and green
# red
# red, green, orange, yellow, pink, blue and green

但无法弄清楚如何实现我想要的输出。有人可以帮忙吗？

Answer 1

仅使用基础R：

sentence_string <- function(x){
  l <- length(x)
  if (l == 1) {
    tolower(x)
  } else {
    x <- tolower(x)
    y <- paste(x[-l], collapse = ', ')
    paste0(c(y, x[l]), collapse = ' and ')
  }
}

，并提供：

> sentence_string(x1)
[1] "red, green and blue"
> sentence_string(x2)
[1] "red, green, orange, yellow and pink"
> sentence_string(x3)
[1] "red and green"
> sentence_string(x4)
[1] "red"
> sentence_string(x5)
[1] "red, green, orange, yellow, pink, blue and green"

Answer 2

我喜欢使用stringi进行这些操作，

library(stringi)

get_string <- function(x){
  y <- paste(x, collapse = ', ')
  y1 <- tolower(stri_replace_last_regex(y, ',', ' and'))
  return(y1)
}

get_string(x1)
#[1] "red, green and blue"

输出一个字符串作为句子

2 个答案: