Question

我一直在努力寻找将ASCII字符转换/解码为可读文本的类。

我在Stack Overflow中找到了这个方法，它将许多字符修复为可读文本。但我仍然在努力，例如：

#&44;
#&46;
#&58;
#&39;

......等等。

我从带有TBXML的XML文件接收数据，XML上的编码是：

iso-8859-1

是否有人将所有 ASCII字符转换/解码为可读文本？

- (NSString *)stringByDecodingXMLEntities {
    NSUInteger myLength = [self length];
    NSUInteger ampIndex = [self rangeOfString:@"&" options:NSLiteralSearch].location;

    // Short-circuit if there are no ampersands.
    if (ampIndex == NSNotFound) {
        return self;
    }
    // Make result string with some extra capacity.
    NSMutableString *result = [NSMutableString stringWithCapacity:(myLength * 1.25)];

    // First iteration doesn't need to scan to & since we did that already, but for code simplicity's sake we'll do it again with the scanner.
    NSScanner *scanner = [NSScanner scannerWithString:self];

    [scanner setCharactersToBeSkipped:nil];

    NSCharacterSet *boundaryCharacterSet = [NSCharacterSet characterSetWithCharactersInString:@" \t\n\r;"];

    do {
        // Scan up to the next entity or the end of the string.
        NSString *nonEntityString;
        if ([scanner scanUpToString:@"&" intoString:&nonEntityString]) {
            [result appendString:nonEntityString];
        }
        if ([scanner isAtEnd]) {
            goto finish;
        }
        // Scan either a HTML or numeric character entity reference.
        if ([scanner scanString:@"&amp;" intoString:NULL])
            [result appendString:@"&"];
        else if ([scanner scanString:@"&apos;" intoString:NULL])
            [result appendString:@"'"];
        else if ([scanner scanString:@"&quot;" intoString:NULL])
            [result appendString:@"\""];
        else if ([scanner scanString:@"&lt;" intoString:NULL])
            [result appendString:@"<"];
        else if ([scanner scanString:@"&gt;" intoString:NULL])
            [result appendString:@">"];
        else if ([scanner scanString:@"&#" intoString:NULL]) {
            BOOL gotNumber;
            unsigned charCode;
            NSString *xForHex = @"";

            // Is it hex or decimal?
            if ([scanner scanString:@"x" intoString:&xForHex]) {
                gotNumber = [scanner scanHexInt:&charCode];
            }
            else {
                gotNumber = [scanner scanInt:(int*)&charCode];
            }

            if (gotNumber) {
                [result appendFormat:@"%C", charCode];

                [scanner scanString:@";" intoString:NULL];
            }
            else {
                NSString *unknownEntity = @"";

                [scanner scanUpToCharactersFromSet:boundaryCharacterSet intoString:&unknownEntity];


                [result appendFormat:@"&#%@%@", xForHex, unknownEntity];

                //[scanner scanUpToString:@";" intoString:&unknownEntity];
                //[result appendFormat:@"&#%@%@;", xForHex, unknownEntity];
                NSLog(@"Expected numeric character entity but got &#%@%@;", xForHex, unknownEntity);

            }

        }
        else {
            NSString *amp;

            [scanner scanString:@"&" intoString:&amp];      //an isolated & symbol
            [result appendString:amp];

             NSString *unknownEntity = @"";
             [scanner scanUpToString:@";" intoString:&unknownEntity];
             NSString *semicolon = @"";
             [scanner scanString:@";" intoString:&semicolon];
             [result appendFormat:@"%@%@", unknownEntity, semicolon];
             NSLog(@"Unsupported XML character entity %@%@", unknownEntity, semicolon);

        }

    }
    while (![scanner isAtEnd]);

finish:
    return result;
}

Answer 1

通常你会让NSXMLparser为你处理这个工作。您不需要手动进行转换。

如果你在NSXMLParser上做谷歌，你会得到很多例子。

将数字字符实体引用转换为可读文本

1 个答案: