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Regex:如何从这个字符串中获取“width”和“height”值,这个字符串正好在“bitwise”值之后?

regex-greedy regex

sudoExclamationExclamation · 技术社区 · 6 年前

假设我有这个字符串:

,"mimeType":"video/mp4;+codecs=\"avc1.42001E,+mp4a.40.2\"","bitrate":353051,"width":640,"height":320,"lastModified":"1543659519195688","contentLength":"24469560","quality":"medium","fps":24,"qualityLabel":"360p","projectionType":"RECTANGULAR","averageBitrate":35300;codecs=\"avc1.64001F,+mp4a.40.2\"","bitrate":987359,"width":1280,"height":640,"lastModified":"1543660211977003","quality":"hd720","fps":24,"qualityLabel":"720p","projectionType":"RECTANGULAR

我需要提取宽度和高度的所有对值,在 "bitrate" 弦。

注意字符串有两次宽度和高度。我要买两双:

"bitrate":353051,"width":640,"height":320

"bitrate":987359,"width":1280,"height":640

“比特率” 价值。如果没有 “比特率”

640,320
1280,640

我把绳子贴在这里了:

https://regex101.com/r/VXAyvV/2

1 回复 | 直到 6 年前

Nick SamSmith1986 6 年前

您可以使用这个regex,它将只匹配 width 和 height bitrate :

"bitrate":\d+,"width":(\d+),"height":(\d+)

宽度和高度将分别记录在第1组和第2组中。

Demo on regex101

Cary Swoveland 6 年前

"bitrate":(?=.*?"width":(?<width>\d+))(?=.*?"height":(?<height>\d+))

Demo

我用PCRE(PHP)正则表达式引擎测试了它,但是它应该可以与所有支持正lookaheads的引擎一起工作,正lookaheads是大多数正则表达式引擎。

"bitrate" 是匹配的),即使它遵循字符串中的高度。中间可能有场 “比特率” 和 "width" “比特率” "height" .

考虑下面的字符串。

"qual":"360p","bitrate":987359,"wt":90,"width":1280,"fps":24,"height":640,"last":"154"

当与regex匹配时,名为 width 将保持 "1280" height 将保持 "640"

regex引擎执行以下操作。

"bitrate":       match '"bitrate":'
(?=              begin a positive lookahead
  .*?            lazily match 0+ chars other than newlines
  "width":       match '"width":'
  (?<width>\d+)  match 1+ digits and save to capture group 'width'
)                end positive lookahead
(?=              begin a positive lookahead
  .*?            lazily match 0+ chars other than newlines
  "height":      match '"height":'
  (?<height>\d+) match 1+ digits and save to capture group 'height'
)                end positive lookahead