ios 搜索关键字高亮显示

注：将以下方法加到NSString的分类里

/**
*  部分子字符串高亮显示(搜索的内容不进行拆分，直接匹配有则显示)
*
*  @param substring  需高亮显示的字符串
*  @param color 高亮颜色
*
*  @return 富文本字符串
*/

- (NSMutableAttributedString *)stringWithHighLightSubstring:(NSString *)substring highLightColor:(UIColor *)color {
    NSMutableAttributedString * attributedString = [[NSMutableAttributedString alloc] initWithString:self];
    NSString * copyTotalString = self;
    NSMutableString * replaceString = [NSMutableString stringWithString:@""];
    for (int i = 0; i < substring.length; i ++) {
        [replaceString appendString:@" "];
    }
    while ([copyTotalString rangeOfString:substring].location != NSNotFound) {
         NSRange range = [copyTotalString rangeOfString:substring];
         [attributedString addAttribute:NSForegroundColorAttributeName value:color range:range];
        if (copyTotalString.length>range.location) {
            copyTotalString = [copyTotalString stringByReplacingCharactersInRange:range withString:replaceString];
        }else {
            copyTotalString = @"";
        }
     }
    return attributedString;
}

/**
*  部分子字符串高亮显示(支持搜索的内容拆分为单个字符串与整体的数据进行比较)
*
*  @param substring  需高亮显示的字符串
*  @param color 高亮颜色
*
*  @return 富文本字符串
*/

- (NSMutableAttributedString *)stringWithPartHighLightSubstring:(NSString *)substring highLightColor:(UIColor *)color {
    NSMutableAttributedString * attributedString = [[NSMutableAttributedString alloc] initWithString:self];
    NSString * copyTotalString = self;
    NSMutableString * replaceString = [NSMutableString stringWithString:@" "];
    for (int i = 0; i < substring.length; i ++) {
        NSString *singleString = [substring substringWithRange:NSMakeRange(i, 1)];
        while ([copyTotalString rangeOfString:singleString].location != NSNotFound) {
             NSRange range = [copyTotalString rangeOfString:singleString];
             //颜色如果统一的话可写在这里，如果颜色根据内容在改变，可把颜色作为参数，调用方法的时候传入
             [attributedString addAttribute:NSForegroundColorAttributeName value:[UIColor orangeColor] range:range];
             copyTotalString = [copyTotalString stringByReplacingCharactersInRange:range withString:replaceString];
         }
    }
    return attributedString;
}