在正则表达式中,您可以轻松地对不同的匹配进行分组"模式匹配"给定的比赛。
while match != nil {
match = source.rangeOfString(regex, options: .RegularExpressionSearch)
if let m = match {
result.append(source.substringWithRange(m)
source.replaceRange(m, with: "")
}
}
上述作品找到了一系列的匹配,但它不能告诉我这个组。例如,如果我搜索封装在""我想要匹配一个"字"但很快就只能获取单词
是否有可能在swift中这样做?
答案 0 :(得分:33)
NSRegularExpression
上的方法是matchesInString
。以下是如何使用它:
let string = "This is my \"string\" of \"words\"."
let re = NSRegularExpression(pattern: "\"(.+?)\"", options: nil, error: nil)!
let matches = re.matchesInString(string, options: nil, range: NSRange(location: 0, length: string.utf16Count))
println("number of matches: \(matches.count)")
for match in matches as [NSTextCheckingResult] {
// range at index 0: full match
// range at index 1: first capture group
let substring = (string as NSString).substringWithRange(match.rangeAtIndex(1))
println(substring)
}
输出:
number of matches: 2
string
words
答案 1 :(得分:7)
如果要收集匹配的字符串,可以使用此选项。 (我的回答来自Nate Cooks非常有帮助的答案。)
针对Swift 2.1进行了更新
extension String {
func regexMatches(pattern: String) -> Array<String> {
let re: NSRegularExpression
do {
re = try NSRegularExpression(pattern: pattern, options: [])
} catch {
return []
}
let matches = re.matchesInString(self, options: [], range: NSRange(location: 0, length: self.utf16.count))
var collectMatches: Array<String> = []
for match in matches {
// range at index 0: full match
// range at index 1: first capture group
let substring = (self as NSString).substringWithRange(match.rangeAtIndex(1))
collectMatches.append(substring)
}
return collectMatches
}
}
针对Swift 3.0进行了更新
extension String {
func regexMatches(pattern: String) -> Array<String> {
let re: NSRegularExpression
do {
re = try NSRegularExpression(pattern: pattern, options: [])
} catch {
return []
}
let matches = re.matches(in: self, options: [], range: NSRange(location: 0, length: self.utf16.count))
var collectMatches: Array<String> = []
for match in matches {
// range at index 0: full match
// range at index 1: first capture group
let substring = (self as NSString).substring(with: match.rangeAt(1))
collectMatches.append(substring)
}
return collectMatches
}}
答案 2 :(得分:4)
这个家伙怎么样,添加为String的扩展名? ))所有匹配,所有组)self = String如果你想不添加扩展名然后添加String参数并将所有self替换为你的参数:)
func matchesForRegexInTextAll(regex: String!) -> [[String]] {
do {
let regex = try NSRegularExpression(pattern: regex, options: [])
let nsString = self as NSString
var resultsFinal = [[String]]()
let results = regex.matchesInString(self,
options: [], range: NSMakeRange(0, nsString.length))
for result in results {
var internalString = [String]()
for var i = 0; i < result.numberOfRanges; ++i{
internalString.append(nsString.substringWithRange(result.rangeAtIndex(i)))
}
resultsFinal.append(internalString)
}
return resultsFinal
} catch let error as NSError {
print("invalid regex: \(error.localizedDescription)")
return []
}
}
答案 3 :(得分:3)
所提供的所有答案都很好,但是我将提供用Swift 2.2编写的MSDN String
扩展名。
注意到差异:
extension String {
func capturedGroups(withRegex pattern: String) -> [String]? {
var regex: NSRegularExpression
do {
regex = try NSRegularExpression(pattern: pattern, options: [])
} catch {
return nil
}
let matches = regex.matchesInString(self, options: [], range: NSRange(location:0, length: self.characters.count))
guard let match = matches.first else { return nil }
// Note: Index 1 is 1st capture group, 2 is 2nd, ..., while index 0 is full match which we don't use
let lastRangeIndex = match.numberOfRanges - 1
guard lastRangeIndex >= 1 else { return nil }
var results = [String]()
for i in 1...lastRangeIndex {
let capturedGroupIndex = match.rangeAtIndex(i)
let matchedString = (self as NSString).substringWithRange(capturedGroupIndex)
results.append(matchedString)
}
return results
}
}
使用:
// Will match "bcde"
"abcdefg".capturedGroups(withRegex: "a(.*)f")
答案 4 :(得分:1)
更新了Swift 4
/**
String extension that extract the captured groups with a regex pattern
- parameter pattern: regex pattern
- Returns: captured groups
*/
public func capturedGroups(withRegex pattern: String) -> [String] {
var results = [String]()
var regex: NSRegularExpression
do {
regex = try NSRegularExpression(pattern: pattern, options: [])
} catch {
return results
}
let matches = regex.matches(in: self, options: [], range: NSRange(location:0, length: self.count))
guard let match = matches.first else { return results }
let lastRangeIndex = match.numberOfRanges - 1
guard lastRangeIndex >= 1 else { return results }
for i in 1...lastRangeIndex {
let capturedGroupIndex = match.range(at: i)
let matchedString = (self as NSString).substring(with: capturedGroupIndex)
results.append(matchedString)
}
return results
}
使用:
// Will match "bcde"
"abcdefg".capturedGroups(withRegex: "a(.*)f")
Github上的要点:https://gist.github.com/unshapedesign/1b95f78d7f74241f706f346aed5384ff