如何通過正則表達式匹配字符串值？

Question

我正在做的應用程序，依賴於html.i代碼中傳遞的HTML文件，所有的數據都顯示在控制檯，但我的問題是如何通過使用正則表達式匹配字符串我不給所有數據的HTML是大 這是值是在控制檯上打印

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        var MacsArray = new Array(); 

       var SortedStations = new Array(
      "AAR","ABZ","AGA","AHO","ALC","LEI","AOI","BCN","BRI","EGC","SXF","BZR","BIQ","BLL","BHX","BLQ","BOD","BOH","BTS","BRE","BES","BDS","BRS","BSL","BRQ","CRL","BZG","CAG","CCF","CND","ORK","CUF","LDY","DNR","DSA","DUB","MME","NRN","EMA","EDI","EIN","FAO","FEZ","FSC","HHN","FUE","GDN","GOA","GRO","PIK","GSE","GRX","LPA","GRZ","GNB","LBC","HAU","IBZ","XRY","FKB","KTW","KUN","KIR","KLU","NOC","KGS","KRK","SUF","ACE","LPP","LCA","LRH","LBA","LIL","LIG","LNZ","LPL","LCJ","LGW","LTN","STN","LDE","MST","MAD","AGP","MLA","MAN","RAK","MRS","FMM","BGY","MPL","MJV","NDR","NTE","NCL","NQY","FNI","OSI","RYG","TRF","OUD","PMO","PMI","BVA","MMX","XCR","PMF","PGF","PEG","PSR","PSA","PDV","PIS","OPO","POZ","PRG","PUY","REU","RHO","RIX","RMI","RDZ","CIA","RZE","SZG","SDR","SCQ","SVQ","SNN","VXO","EBU","NYO","VST","SZZ","TMP","TNG","TFS","TLN","TUF","TPS","TRS","TRN","VLC","VLL","TSF","VRN","VOL","WRO","ZAD","ZAZ","RLG","KSD","CSO","SFT","TLL","HUY","RJK","SKG","VCE","VNO","CHQ","CFU","LEJ" 
       ); 

       var Stations = new Array(); 
       Stations["AAR"] = new Station("AAR", "", "Aarhus", true, true, new Array("AGP","RYG","STN")); 
Stations["AGP"] = new Station("AGP", "", "Malaga", true, true, new Array("AAR","BCN","BGY","BHX","BLL","BLQ","BOH","BRE","BRS","BTS","BVA","CRL","CSO","DUB","EDI","EIN","EMA","FMM","GSE","HAU","HHN","IBZ","KRK","LBA","LPL","MAN","MMX","MRS","MST","NRN","NYO","ORK","PIK","PSA","RYG","SCQ","SDR","SNN","STN","SXF","TMP","TRF","VCE","VLC","VLL","VST","WRO","ZAZ")); 
Stations["RYG"] = new Station("RYG", "", "Oslo (Rygge)", true, true, new Array("AAR","AGP","ALC","BCN","BVA","BZR","CIA","CRL","DUB","FAO","FMM","GDN","HHN","KGS","KRK","KUN","LGW","LPL","LRH","MAD","MAN","NCL","NYO","PMI","PMO","POZ","RIX","SKG","STN","SXF","TLL","TMP","VCE","VLC","WRO","XCR","ZAD")); 


i done this for match all string value in code 
- (void)applicationDidFinishLaunching:(UIApplication *)application { 
    [self sendRequest ]; 
    //Extraction of valid mail ids 
    //NSString * searchString = @" para.g@gmail.com sourabh_84368@gmail.com abc@def.in abcd@yahoomail.com mobisoft@mail.in andy@rediffmail.com"; 
    NSString * searchString = loginstatus; 
    NSString *regexString = @"[a-z0-9_.%]+@[a-z0-9_.%]+\\.[a-z][a-z][a-z]"; 
    //NSString *regexString = @"Stations\["(.*)"\] = new Station\((.*)\);"; 
    NSArray *matchArray = nil; 
    matchArray = [searchString componentsMatchedByRegex:regexString]; 
    NSLog(@"matchArray: %@", matchArray); 
    // Override point for customization after application launch 
    //NSString* source = @"Test;12;Y"; 
// NSArray* columns = [source componentsSeparatedByRegex:@";\\s*"]; 
// NSLog([columns description]); 
// [window makeKeyAndVisible]; 
} 

懇求有人幫我在這

Answer 1

• 如果是iOS4的+開發，使用NSRegularExpression類
• 如果你需要的目標以前的iOS版本：
  • 您可以嘗試使用NSPredicate，它支持通過MATCHES運算符的ICU RegEx語法。但它只允許你測試字符串是否匹配，並且不能進行替換或者提取匹配的字符串，所以這是非常有限的。
  • 您可以使用第三方庫，例如RegExKit

Answer 2

使用NSPredicate反對正則表達式匹配的字符串。

NSString *searchString = @"loginStatus"; 
NSString *regexString = @"[a-z0-9_.%]+@[a-z0-9_.%]+\\.[a-z][a-z][a-z]"; 
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"self matches %@", regexString]; 
BOOL isStringValid = [predicate evaluateWithObject:searchString]; 

Answer 3

如果您嘗試使用正則表達式來解析HTML，您可能會以錯誤的方式解決這個問題。已經有專門的解析器用於此目的，比如NSXMLParser，在您的應用程序中使用NSXMLParser比重新編寫輪盤編寫正則表達式以從HTML中獲取數據更容易。