如何通過正則表達式匹配字符串值？

Question

我正在制作依賴於html.i的應用程序，將html文件傳遞給代碼，所有數據都顯示在控制台中，但是我的問題是如何通過使用正則表達式匹配字符串我沒有給html所有數據，這是很大的價值在控制台上打印

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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];
}

請有人幫我

Answer 1

使用NSPredicate將字符串與正則表達式匹配。

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 2

• 如果您正在為iOS4 +開發，請使用NSRegularExpression類
• 如果您需要定位以前的iOS版本：
  • 您可以嘗試使用通過MATCHES運算符支持ICU RegEx語法的NSPredicate 。 但是它僅允許您測試字符串是否匹配，並且不能進行替換也不能提取匹配的字符串，因此這是非常有限的。
  • 您可以使用RegExKit類的第三方庫

Answer 3

如果您嘗試使用正則表達式來解析HTML，則可能是錯誤的方法。 已經有專用的解析器，例如NSXMLParser，與重新發明用正則表達式從HTML中獲取數據的發明相比，NSXMLParser相對於您更容易在應用中使用。