ios开发中使用正则表达式识别处理字符串中的URL

在项目中经常有识别文本中url并可以点击进行网页链接的需求。我们需要适当的处理带url的字符串

代码如下：

-(void)createUI

{

    textView=[[UITextView
alloc]initWithFrame:CGRectMake(18,
100, self.view.bounds.size.width-36,
100)];

    [textView setEditable:NO];

    [self.view
addSubview:textView];

    [self subStr:@"我是一段中文https://github.com/TinyQ我还是一段中文阿里科技屌丝拉法基是拉萨江东父老阿斯蒂芬阿斯蒂芬四缸发动机https://www.baidu.com发送"];

 

}

-(NSMutableAttributedString*)subStr:(NSString *)string

{

    NSError *error;

    //可以识别url的正则表达式

    NSString *regulaStr =
@"((http[s]{0,1}|ftp)://[a-zA-Z0-9\\.\\-]+\\.([a-zA-Z]{2,4})(:\\d+)?(/[a-zA-Z0-9\\.\\-~!@#$%^&*+?:_/=<>]*)?)|(www.[a-zA-Z0-9\\.\\-]+\\.([a-zA-Z]{2,4})(:\\d+)?(/[a-zA-Z0-9\\.\\-~!@#$%^&*+?:_/=<>]*)?)";

    NSRegularExpression *regex = [NSRegularExpression
regularExpressionWithPattern:regulaStr

                                                                          
options:NSRegularExpressionCaseInsensitive

                                                                            
error:&error];

    NSArray *arrayOfAllMatches = [regex
matchesInString:string options:0
range:NSMakeRange(0, [string
length])];

    //NSString *subStr;

    NSMutableArray *arr=[[NSMutableArray
alloc]init];

    NSArray *rangeArr=[[NSMutableArray
alloc]init];

    

    for (NSTextCheckingResult *match
in arrayOfAllMatches)

    {

        NSString* substringForMatch;

        substringForMatch = [string substringWithRange:match.range];

        [arr addObject:substringForMatch];

       

    }

    NSString *subStr=string;

    for (NSString *str
in arr)

    {

       subStr=[subStr  stringByReplacingOccurrencesOfString:str
withString:@"网页链接"];

    }

   rangeArr=[self
rangesOfString:@"网页链接"
inString:subStr];

    

//    //计算大小

    UIFont *font = [UIFont
systemFontOfSize:15];

    NSMutableAttributedString *attributedText;

  

    attributedText=[[NSMutableAttributedString
alloc]initWithString:subStr
attributes:@{NSFontAttributeName :font}];

    

    for(NSValue *value
in rangeArr)

    {

        NSInteger index=[rangeArr
indexOfObject:value];

        NSRange range=[value
rangeValue];

         [attributedText addAttribute:
NSLinkAttributeName value: [NSURL
URLWithString:[NSString
stringWithFormat:@"%@",[arr
objectAtIndex:index]]] range:range];

    }

   return attributedText;

}

//获取查找字符串在母串中的NSRange

- (NSArray *)rangesOfString:(NSString *)searchString inString:(NSString *)str {

    

        NSMutableArray *results = [NSMutableArray
array];

    

       NSRange searchRange =
NSMakeRange(0, [str
length]);

    

       NSRange range;

    

    while ((range = [str
rangeOfString:searchString options:0
range:searchRange]).location !=
NSNotFound) {

      

                [results addObject:[NSValue
valueWithRange:range]];

        

               searchRange = NSMakeRange(NSMaxRange(range), [str
length] - NSMaxRange(range));

        

            }

    

    return results;

}