我的正则表达式没有得到正确的结果,我找不到错误的地方。
let ori_str = "abcXabcYabcZ" // there are 3 Capital character
let pattern = "[A-Z]"
let regular = try!NSRegularExpression(pattern: pattern, options: .caseInsensitive)
let results = regular.matches(in: ori_str, options: .reportProgress , range: NSMakeRange(0, ori_str.characters.count))
print("results have: \(results.count) count") // log 'result have: 12 count' why 12 without 3 ???
我想获取大写字符,然后将它们替换为 -(大写字符的小写字符)-
,但我的正则表达式的结果是 console 12 count of Capital Characters。
1)你看,应该是3,哪里错了?
2) 如何将大写字母替换为-(大写字母的小写字母)-
?
加法-1
下面是所有的 NSRegularExpression.Options
:
public static var caseInsensitive: NSRegularExpression.Options { get }
public static var allowCommentsAndWhitespace: NSRegularExpression.Options { get }
public static var ignoreMetacharacters: NSRegularExpression.Options { get }
public static var dotMatchesLineSeparators: NSRegularExpression.Options { get }
public static var anchorsMatchLines: NSRegularExpression.Options { get }
public static var useUnixLineSeparators: NSRegularExpression.Options { get }
public static var useUnicodeWordBoundaries: NSRegularExpression.Options { get }`
最佳答案
您需要进行区分大小写的匹配。 将选项从 .caseInsensitive 更改为 []。
NSRegularExpression.Options 是一个 OptionSet,它允许指定零个或多个值。当传递零或多于一时,使用数组文字语法。 请参阅:https://developer.apple.com/reference/swift/optionset
let ori_str = "abcXabcYabcZ" // there are 3 Capital character
let pattern = "[A-Z]"
let regular = try!NSRegularExpression(pattern: pattern, options: [])
let results = regular.matches(in: ori_str, options: .reportProgress, range: NSMakeRange(0, ori_str.characters.count))
print("results have: \(results.count) count")
关于您的第二个标准,使用正则表达式组将涵盖:
let ori_str = "abcXabcYabcZ" // there are 3 Capital character
let pattern = "([A-Z])"
let regular = try!NSRegularExpression(pattern: pattern)
let replaced = regular.stringByReplacingMatches(
in: ori_str, options: [],
range: NSMakeRange(0, ori_str.characters.count),
withTemplate: "-$1-").lowercased()
print("Uppercase characters replaced: \(replaced)")
对于更高级的内容,您需要为每个匹配添加额外的自定义代码:
extension String {
func replace(regex: NSRegularExpression, with replacer: (_ match:String)->String) -> String {
let str = self as NSString
let ret = str.mutableCopy() as! NSMutableString
let matches = regex.matches(in: str as String, options: [], range: NSMakeRange(0, str.length))
for match in matches.reversed() {
let original = str.substring(with: match.range)
let replacement = replacer(original)
ret.replaceCharacters(in: match.range, with: replacement)
}
return ret as String
}
}
let ori_str = "abcXabcYabcZ" // there are 3 Capital character
let pattern = "[A-Z]"
let regular = try!NSRegularExpression(pattern: pattern)
let replaced = ori_str.replace(regex: regular) { "-\($0.lowercased())-" }
print("Uppercase characters replaced: \(replaced)")
关于ios - RegExp 结果不是我的预期,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/41294709/