Question

是否可以从网址获取特定值并将其保存到csv？

我有一个txt文件，其中一列包含这样的网址

我尝试收集价值，例如奖励的价值和支持者的数量。最终文件应该有两列，如下所示

10,15,30,50     17,9,9

Answer 1

以下是使用rvest包的解决方案：

library(rvest)
url.parse<-read_html("https://www.kickstarter.com/projects/1154444340/god-in-new-york/description")

reward<-url.parse%>%
 html_nodes("h5")%>%
 html_text(trim=TRUE)
reward
[1] "$10 reward" "$15 reward" "$30 reward" "$50 reward"

 backers<-url.parse%>%
 html_nodes("span.num-backers.mr1")%>%
 html_text(trim=TRUE)

backers
[1] "17 backers" "9 backers"  "9 backers"  "30 backers"

如果你想在一个数据帧中同时使用：

df1<-data.frame(do.call(cbind,lapply(c("span.num-backers.mr1","h5"),
                     function(i) {
                        url.parse %>%
                             html_nodes(i) %>%
                             html_text(trim=TRUE)
                     })))
df1

   X1         X2
1 17 backers $10 reward
2  9 backers $15 reward
3  9 backers $30 reward
4 30 backers $50 reward

如果您有网址列表，可以按以下步骤操作：

url_kick<-c("https://www.kickstarter.com/projects/1154444340/god-in-new-york/description","https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured")
data.frame(do.call(rbind,lapply(url_kick,function(url_name){
    kk<-data.frame(do.call(cbind,lapply(c("span.num-backers.mr1","h5"),
                                        function(i) {
                                            read_html(url_name) %>%
                                                html_nodes(i) %>%
                                                html_text(trim=TRUE)
                                        })))
    return(cbind(kk,urlname=url_name))})))
          X1                                  X2                                                                                                      urlname
1  17 backers                          $10 reward                                  https://www.kickstarter.com/projects/1154444340/god-in-new-york/description
2   9 backers                          $15 reward                                  https://www.kickstarter.com/projects/1154444340/god-in-new-york/description
3   9 backers                          $30 reward                                  https://www.kickstarter.com/projects/1154444340/god-in-new-york/description
4  30 backers                          $50 reward                                  https://www.kickstarter.com/projects/1154444340/god-in-new-york/description
5    1 backer                         Josh Ginter https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
6    1 backer              Project by Josh Ginter https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
7   3 backers   Pledge $1 or more\n\nAbout $1 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
8   3 backers                        About $1 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
9   3 backers   Pledge $1 or more\n\nAbout $1 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
10  3 backers                        About $1 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
11  6 backers   Pledge $5 or more\n\nAbout $5 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
12  6 backers                        About $5 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
13   1 backer   Pledge $5 or more\n\nAbout $5 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
14   1 backer                        About $5 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
15  3 backers Pledge $10 or more\n\nAbout $10 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
16  3 backers                       About $10 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
17  3 backers Pledge $10 or more\n\nAbout $10 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
18  3 backers                       About $10 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
19  6 backers Pledge $25 or more\n\nAbout $25 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
20  6 backers                       About $25 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
21   1 backer Pledge $25 or more\n\nAbout $25 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured
22   1 backer                       About $25 USD https://www.kickstarter.com/projects/1685845978/creature-and-hand-1-an-accordion-comic?ref=category_featured

从网页中提取值

1 个答案: