使用 NSScanner 查找短语的下一个匹配项

我使用以下代码在 HTML 文件中查找特定代码行：

NSURL *requestTimetableURL = [NSURL URLWithString:@"http://www.dhsb.org/index.phtml?d=201435"];
NSLog(@"Loaded Timetable");
NSError *error;
NSString *page = [NSString stringWithContentsOfURL:requestTimetableURL 
                                              encoding:NSASCIIStringEncoding
                                                 error:&error];

[webView loadHTMLString:page baseURL:requestTimetableURL];

NSString* Period1;

NSScanner *htmlScanner =  [NSScanner scannerWithString:page];

[htmlScanner scanUpToString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner scanString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner scanUpToString:@"</FONT>" intoString:&Period1];

period1label.text= Period1;

NSLog(@"Collected Period 1 Data: %@", Period1);

NSScanner *htmlScanner2 =  [NSScanner scannerWithString:page];

NSString* Period2;

[htmlScanner2 scanUpToString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner2 scanString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner2 scanUpToString:@"</FONT>" intoString:&Period2];

period2label.text= Period2;

NSLog(@"Collected Period 2 Data: %@", Period2);

您会注意到要查找的两个字符串是相同的。这是因为没有什么可以真正区分这两行代码。有两场比赛：

<P align=center><STRONG><FONT color=#c00000>

在我的代码中。如何查找“Period 1”中的第一场比赛和“Period 2”中的第二场比赛？

Thanks!

在使用第二个扫描仪之前，请设置scanLocation超出该短语的第一个实例的开头，如下所示：

[htmlScanner2 setScanLocation:(htmlScanner1.scanLocation + 1)];

编辑：只是一个想法 - 你为什么要使用两台扫描仪？只需使用一台扫描仪，如下所示：

NSURL *requestTimetableURL = [NSURL URLWithString:@"http://www.dhsb.org/index.phtml?d=201435"];
NSLog(@"Loaded Timetable");
NSError *error;
NSString *page = [NSString stringWithContentsOfURL:requestTimetableURL 
                                              encoding:NSASCIIStringEncoding
                                                 error:&error];

[webView loadHTMLString:page baseURL:requestTimetableURL];

NSString* Period1;

NSScanner *htmlScanner =  [NSScanner scannerWithString:page];

[htmlScanner scanUpToString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner scanString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner scanUpToString:@"</FONT>" intoString:&Period1];

period1label.text= Period1;

NSLog(@"Collected Period 1 Data: %@", Period1);

NSString* Period2;

[htmlScanner scanUpToString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner scanString:@"<P align=center><STRONG><FONT color=#c00000>" intoString:NULL];
[htmlScanner scanUpToString:@"</FONT>" intoString:&Period2];

period2label.text= Period2;

NSLog(@"Collected Period 2 Data: %@", Period2);