有沒有辦法在字串中檢索以 @ 符號為前綴的單詞陣列？
"@City == xyz AND @Hobby == 園藝" -> ["@City","@Hobby"]
我嘗試了以下兩種方法，但都回傳一個空陣列。
let regexp = "/@\\w*/g"
func matches(for regex: String, in text: String) -> [String] {
do {
let regex = try NSRegularExpression(pattern: regex)
let results = regex.matches(in: text,range: NSRange(text.startIndex..., in: text))
return results.map {
String(text[Range($0.range, in: text)!])
}
} catch let error {
print("invalid regex: \(error.localizedDescription)")
return []
}
}
extension String {
func regex (pattern: String) -> [String] {
do {
let regex = try NSRegularExpression(pattern: pattern, options: NSRegularExpression.Options(rawValue: 0))
let nsstr = self as NSString
let all = NSRange(location: 0, length: nsstr.length)
var matches : [String] = [String]()
regex.enumerateMatches(in: self, options: NSRegularExpression.MatchingOptions(rawValue: 0), range: all) {
(result : NSTextCheckingResult?, _, _) in
if let r = result {
let result = nsstr.substring(with: r.range) as String
matches.append(result)
}
}
return matches
} catch {
return [String]()
}
}
}
uj5u.com熱心網友回復：
正如@jnpdx 在評論中暗示的那樣，您的基本問題是您的regexp字串包含來自另一種語言的控制元素。以下應該可以解決您的問題：
let regexp = "@\\w*"
您還會陷入不必要的 try-catch 陳述句和基于 Objective-C 及其相關型別轉換的過時 API 中。以下應該做：
func matches(for regex: String, in text: String) -> [String] {
var result = [String]()
var startIndex = text.startIndex
let endIndex = text.endIndex
while let range = text.range(of: regex,
options: .regularExpression,
range: startIndex ..< endIndex)
{
result.append(String(text[range]))
startIndex = range.upperBound
}
return result
}
轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/470744.html
上一篇：C#基礎和字串問題