正则表达式基础篇
正则使用-OC篇

返回所有匹配结果

func matches(pattern: String, validate: String) -> [String] {
    do {
        let regex = try NSRegularExpression(pattern: pattern, options: [])
        let matches = regex.matches(in: validate, options: [], range: NSMakeRange(0, validate.count))
        var datas: [String] = []
        matches.forEach { result in
            let startIdx = validate.index(validate.startIndex, offsetBy:result.range.location)
            let endIdx = validate.index(validate.startIndex, offsetBy: result.range.length - 1)
            let newStr = validate[startIdx...endIdx]
            datas.append("\(newStr)")
            
//            let newStr = (validate as NSString).substring(with: result.range)
//            datas.append(newStr)
        }
        
        return datas
    }
    catch {
        return []
    }
}

测试用例：

let pattern = "^(10001|10002)$"
let validate = "10001"
let newStr = matches(pattern: pattern, validate: validate)
print("匹配结果：\(newStr)")

打印结果：

匹配结果：["10001"]

获取第1个匹配的结果

func firstMatch(pattern: String, validate: String) -> String {
    do {
        let regex = try NSRegularExpression(pattern: pattern, options: .caseInsensitive)
        let result = regex.firstMatch(in: validate, range: NSMakeRange(0, validate.count))
        
        guard let result else { return "" }
        
        let startIdx = validate.index(validate.startIndex, offsetBy:result.range.location)
        let endIdx = validate.index(validate.startIndex, offsetBy: result.range.length - 1)
        let newStr = validate[startIdx...endIdx]
        
        return "\(newStr)"
    } catch {
        return ""
    }
}

测试用例：

let pattern = "runoob(?=[\\d+])"
let validate = "runoob12runoobdrunooB3"
let newStr = firstMatch(pattern: pattern, validate: validate)
print("匹配结果：\(newStr)")

打印结果：

匹配结果：runoob

获取匹配的数量

func numberOfMatches(pattern: String, validate: String) -> Int {
    do {
        // options: [] 区分大小写，严格匹配
        // options: .caseInsensitive 不区分大小写
        let regex = try NSRegularExpression(pattern: pattern, options: .caseInsensitive)
        let number = regex.numberOfMatches(in: validate, range: NSMakeRange(0, validate.count))
        return number
    } catch {
        return 0
    }
}

测试用例：

let pattern = "runoob(?=[\\d+])"
let validate = "runoob12runoobdrunooB3"
let matchCount = numberOfMatches(pattern: pattern, validate: validate)
print("匹配数量：\(matchCount)")

打印结果：

// options: .caseInsensitive 不区分大小写
匹配数量：2

// options: [] 区分大小写，严格匹配
匹配数量：1

字符串正则替换

func matchReplace(pattern: String, validate: String, replacing: String) -> String {
    do {
        let regex = try NSRegularExpression(pattern: pattern, options: .caseInsensitive)
        let modified = regex.stringByReplacingMatches(in: validate, options: .reportProgress, range: NSMakeRange(0, validate.count), withTemplate: replacing)
        return modified
    } catch {
        return validate
    }
}

测试用例：

let replacePattern = "[0-9]+"
let validateStr = "12-ab-3-c"
let replacingStr = "ufo"
let modified = matchReplace(pattern: replacePattern, validate: validateStr, replacing: replacingStr)
print("替换后：\(modified)")

打印结果：

替换后：ufo-ab-ufo-c