如何在Objective-C中解析字符串

Question

我想解析一个字符串来替换一些元素。
如果我的字符串包含<ol>那么我想解析<li>元素以将它们替换为数字。

我知道我可以使用rangeOfString检查包含的String。

if ([myString rangeOfString:@"<ol>"].location != NSNotFound) {
    //Do stuff here  
}

如何仅解析<ol>和</ol>元素之间？

编辑1：这是我的解决方案

- (NSString *)parseOrderedList:(NSString *)str {


NSMutableString *html = [NSMutableString stringWithCapacity:[str length]];

NSScanner *scanner = [NSScanner scannerWithString:str];
NSString *tempText = nil;

while (![scanner isAtEnd])
{
    [scanner scanUpToString:@"<ol>" intoString:&tempText];
    [scanner scanUpToString:@"</ol>" intoString:&tempText];


    if (tempText != nil) {
        [html appendString:tempText];
        html = [[[html stringByReplacingOccurrencesOfString:@"</li>" withString:@" "] mutableCopy] autorelease];

            while ([html rangeOfString:@"<li>"].location != NSNotFound) {
                html = [[[html stringByReplacingOccurrencesOfString:@"<li>" withString:[NSString stringWithFormat:@"%i.", i]] mutableCopy] autorelease];
                i++;
            }

    }


    if (![scanner isAtEnd])
        [scanner setScanLocation:[scanner scanLocation] + 0];

    tempText = @" ";

}

return html;
}  

但是我该如何更换

当前循环数？ 我每次都得到第一次。

Answer 1

做这个

NSString * aString = @"your string";
NSMutableArray *substrings = [NSMutableArray alloc]init];
NSScanner *scanner = [NSScanner scannerWithString:aString];
[scanner scanUpToString:@"<ol>" intoString:nil]; // Scan all characters before <ol>
while(![scanner isAtEnd]) 
{
  NSString *substring = nil;
  [scanner scanString:@"<ol>" intoString:nil]; // Scan the <ol> character
  if([scanner scanUpToString:@"</ol>" intoString:&substring]) 
  {
  // If the space immediately followed the <ol>, this will be skipped
  [substrings addObject:substring];
  }
 [scanner scanUpToString:@"<ol>" intoString:nil]; // Scan all characters before next <ol>
}

你在nsmutablearray中有一个字符串，可以用来替换你的字符串

其他标签可以重复相同的方法