Question

我有currentString的动态字符串。例如，currenttring如：

<html><head><title></title><meta content="width=320.000000, initial-scale=0.47, maximum-scale=1.0, user-scalable=1" name="viewport"></head><body><table width="510" cellpadding="0" cellpadding="0"><tr><td valign="top"><p><a href="http://erhandemirci.blogspot.com/masak-in-baskani-neden-gorevden-alindi-haberi-828402.html"><img src="http://erhandemirci.blogspot.com/images//news/r-farukeliedioglu-300200-828402.jpg" width="72" height="48" style="border: 1px #000000 solid;" hspace="2" align="left"></a>content...........</p> <p> </p> </td></tr></table></body></html>

我想将表格标签的宽度从510更改为0.我尝试了以下代码，但它无法正常工作。

NSString *currentString = @"<html><...width > <table width="" .... > dynamic string";

    // Regular expression to find "word characters" enclosed by {...}:
    NSRegularExpression *regex;
    regex = [NSRegularExpression regularExpressionWithPattern:@"\\table width=\"(\\w+)\\\""
                                                      options:0
                                                        error:NULL];

    NSMutableString *modifiedString = [currentString mutableCopy];
    __block int offset = 0;
    [regex enumerateMatchesInString:currentString
                            options:0
                              range:NSMakeRange(0, [currentString length])
                         usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
                             // range = location of the regex capture group "(\\w+)" in currentString:
                             NSRange range = [result rangeAtIndex:1];
                             // Adjust location for modifiedString:
                             range.location += offset;

                             // Get old word:
                             NSString *oldWord = [modifiedString substringWithRange:range];

                             // Compute new word:
                             // In your case, that would be
                             // NSString *newWord = [self replaceWord:oldWord];
                             NSString *newWord =@"0";

                             // Replace new word in modifiedString:
                             [modifiedString replaceCharactersInRange:range withString:newWord];
                             // Update offset:
                             offset += [newWord length] - [oldWord length];
                         }
     ];


    NSLog(@"modified%@", modifiedString);

Answer 1

你得到的几乎是正确的，只有@"\\table ...应该是@"\\<table ... 在模式中：

regex = [NSRegularExpression regularExpressionWithPattern:@"\\<table width=\"(\\w+)\\\""
                                                  options:0
                                                    error:NULL];

这将<table width="NNN"取代<table width="0"任意NNN。

请注意，通常不建议使用正则表达式解析HTML。使用专用的HTML解析器可能是更好的方法。

Answer 2

我不知道RegEx。我会使用NSMutableString

等replaceOccurrencesOfString:withString:options:range:方法解决此问题

替换html字符串中的特定单词

2 个答案: