NSMutableAttributedString 的使用方法，设置格式

NSMutableAttributedString *attrString = [[NSMutableAttributedString alloc] initWithString:title];

    NSRange range = NSMakeRange(0, [attrString length]);

[attrString beginEditing];

    [attrString addAttribute:NSLinkAttributeName value:aURL range:range];
// make the text appear in blue

    [attrString addAttribute:NSForegroundColorAttributeName value:[NSColor blueColor] range:range];
// next make the text appear with an underline

    [attrString addAttribute:NSUnderlineStyleAttributeName value:[NSNumber numberWithInteger:NSSingleUnderlineStyle] range:range];
// allow truncation

    NSMutableParagraphStyle *ps = [[NSParagraphStyle defaultParagraphStyle] mutableCopy];

    [ps setLineBreakMode:NSLineBreakByTruncatingTail];

    [attrString addAttribute:NSParagraphStyleAttributeName value:ps range:range];

    [ps release];
[attrString endEditing];
return [attrString autorelease];    

转载自：http://blog.csdn.net/ch_soft/article/details/6877508