创建使用NSRegularExpression的模式

Question

Swift 4.4

我想使用NSAttributedString创建NSRegularExpression

~This two~ are *bold text* and different <textcolor> and ~strikethrough~ and _italic (word*)_ ~abc~

像这样，

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我可以创建和分配属性，但问题是我不知道如何使用NSRegularExpression，但我在雷恩德利希文章的帮助下尝试了许多逻辑。

我试过的一些逻辑。

(1) "(^|\\s|\\b)*(\\S).*(\\S)*($|\\s|\\b)"
(2) "(\\~(.*?)\\~)"
(3) "\\sand\\b"
(4) "(?:^|\\s|$)#[\\p{L}0-9_]*"
(5) "(?:^\\s+)|(?:\\s+$)"

我只需要一种模式的bold 或 italic 或 strikethrough

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更新

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案例1:

let string = "~This two~ are *bold text* and different <textcolor> and ~strikethrough~ and _italic (word*)_ ~abc~"
let pattern = "((^|)~(.*?)(\\S+)~($|\\s))"

产量如下，

Pattern: ((^|)~(.*?)(\S+)~($|\s))
~This two~ 
~strikethrough~ 
~abc~

案例2:

let string = "~This two~ are *bold text* and different <textcolor> and ~strikethrough~ and _italic (word*)_ ~abc~"
let pattern = "((^|)~(.?)(\\S+)~($|\\s))" //here '*' removed

产量如下，

Pattern: ((^|)~(.?)(\S+)~($|\s))
~strikethrough~ 
~abc~

提前谢谢。

更新2

我找到了答案

Answer 1

我无法将模式组合成一个或(|)，并使它们正确匹配，但是如果我一个接一个地匹配它们，它就会工作。

let string = "~This two~ are *bold text* and different <textcolor> and ~strikethrough~ and _italic (word*)_ ~abc~"
let textPattern = "[:alpha:][:punct:][:space:]"
let range = NSRange(location: 0, length: string.utf16.count)
let patterns:[String] = ["(?:~([\(textPattern)]*)~)", "(?:\\*([\(textPattern)]*)\\*)", "(?:<([\(textPattern)]*)>)", "(?:_([\(textPattern)]*)_)"]

for pattern in patterns {
    let regex = try! NSRegularExpression(pattern: pattern)
    regex.enumerateMatches(in: string, range: range, using: { (result, flag, pointer) in 
        if let result = result { 
            for i in 1..<result.numberOfRanges {
                let srange = Range(result.range(at: i))! 
                let start = String.Index(encodedOffset: srange.lowerBound)
                let end = String.Index(encodedOffset: srange.upperBound)
                let substr = String(string[start..<end])
                print("\(result.range(at: i)) => \(substr)")
            }
        }
    })
}

输出

{1，8} =>这两个 {58，13} =>划线 {95，3} => abc {16，9} =>粗体文本 {42，9} =>文本颜色 {78，14} =>斜体(字*)

更新:将我的模式更改为不包括格式字符、~、*等，并在示例中改进输出，以更清楚地显示匹配的正确数量和匹配的内容。

Answer 2

这一守则应适用于：

let string = "~This two~ are *bold text* and different <textcolor> and ~strikethrough~ and _italic (word*)_ ~abc~"

let embedded = ".*?"

let strikeThroughGroupName = "strikethroughGroupName"
let boldGroupName = "boldGroupName"
let colorGroupName = "colorGroupName"
let italicGroupName = "italicGroupName"
let groupNames = [strikeThroughGroupName, boldGroupName, italicGroupName, colorGroupName]

let pattern = "(~(?<\(strikeThroughGroupName)>\(embedded))~)|(<(?<\(colorGroupName)>\(embedded))>)|(_(?<\(italicGroupName)>\(embedded))_)|(\\*(?<\(boldGroupName)>\(embedded))\\*)"

print("Pattern: \(pattern)")

do {
    let regex = try NSRegularExpression(pattern: pattern, options: [])
    let matches = regex.matches(in: string, options: [], range: NSRange(location: 0, length: string.utf16.count))
    matches.forEach { (aMatch) in

        if let groupFound = groupNames.first(where: { aMatch.range(withName: $0).location != NSNotFound }),
            let range = Range(aMatch.range(withName: groupFound), in: string) {
            let textFound = string[range]
            print("Found: \(textFound) with effect: \(groupFound) at NSRange: \(aMatch.range(withName: groupFound))")
        }
        let fullNSRange = aMatch.range
        if let fullRange = Range(fullNSRange, in: string) {
            let textFound = string[fullRange]
            print("Full Text Found: \(textFound)")
        }
    }
} catch {
    print("Regex error: \(error)")
}

输出：

$>Pattern: (~(?<strikethroughGroupName>.*?)~)|(<(?<colorGroupName>.*?)>)|(_(?<italicGroupName>.*?)_)|(\*(?<boldGroupName>.*?)\*)
$>Found: This two with effect: strikethroughGroupName at NSRange: {1, 8}
$>Full Text Found: ~This two~
$>Found: bold text with effect: boldGroupName at NSRange: {16, 9}
$>Full Text Found: *bold text*
$>Found: strikethrough with effect: strikethroughGroupName at NSRange: {59, 13}
$>Full Text Found: ~strikethrough~
$>Found: italic (word*) with effect: italicGroupName at NSRange: {79, 14}
$>Full Text Found: _italic (word*)_
$>Found: abc with effect: strikethroughGroupName at NSRange: {96, 3}
$>Full Text Found: ~abc~

边注：

·我使用了组名(可用于regex)。

它的结构是(?<groupName>groupToCapture)。

·我使用embedded作为快速测试工具。它不可能涵盖所有的案件。例如，它没有涵盖string中行的更改情况。如果它是<text\ncolor> (有一个断线)，它将不匹配。在那里，如果需要，可以使用希望包含断线的正则表达式。

Answer 3

我为我自己的问题找到了一个答案，我会用一个例子来解释它，这样你就可以自己尝试了。

在这里，

    //Some randome bunch of words
let string = "1. *うちに* comes from the ~kanji~ *内* which mean “inside” or “within” and has _two distinct_ meanings in Japanese. 2. Firstly, it shows that something happens within ~a~ period of time. “While” something is happening, you do an action.~Very minimal as~ far as features tha *t* are supported in the Web version. It works in a pinch, if you’re in a hurry and ne. Nice~"

//to find words which are suppose to be stricked using '~' character
let pattern = "~[^\\s](.*?[^\\s])??~"

let regex = try! NSRegularExpression(pattern: pattern, options: [])
let matches = regex.matches(in: string, options: [], range: NSRange(location: 0, length: string.utf16.count))
matches.forEach { (aMatch) in
    let matchedRange = aMatch.range(at: 0)
    let matchingText = (string as NSString).substring(with: matchedRange)
    print(matchingText)
}

非常感谢

，(1) 莱姆 (2) 乔基姆·丹尼尔森 (3) 编码列车

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