Turns HTML into an attributed string with a custom font and paragraph spacing

HTMLtoAttributedString.m

// Omar Zouai | https://omarzouai.com/

- (NSMutableAttributedString*)htmlToAttributed:(NSString*)html font:(UIFont*)font paragraphSpacing:(CGFloat)pSpacing {
    NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithData:[html dataUsingEncoding:NSUTF8StringEncoding] options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute:@(NSUTF8StringEncoding)} documentAttributes:nil error:nil];
    [string beginEditing];
    NSMutableParagraphStyle *pStyle = [[NSMutableParagraphStyle defaultParagraphStyle] mutableCopy];
    [pStyle setParagraphSpacing:pSpacing];
    
    [string enumerateAttributesInRange:NSMakeRange(0, string.length) options:nil usingBlock:^(NSDictionary *attrs, NSRange range, BOOL *stop) {
        UIFont *theFont = [attrs objectForKey:@"NSFont"];
        UIFontDescriptor *desc = theFont.fontDescriptor;
        UIFontDescriptorSymbolicTraits descSym = desc.symbolicTraits;
        BOOL isBold = (descSym & UIFontDescriptorTraitBold) != 0;
        BOOL isItalic = (descSym & UIFontDescriptorTraitItalic) != 0;
        UIFont *targetFont = font;
        if(isBold && isItalic) {
            UIFontDescriptor *fontD = [font.fontDescriptor fontDescriptorWithSymbolicTraits:UIFontDescriptorTraitBold | UIFontDescriptorTraitItalic];
            targetFont = [UIFont fontWithDescriptor:fontD size:0];
            
        } else if(isBold) {
            UIFontDescriptor *fontD = [font.fontDescriptor fontDescriptorWithSymbolicTraits: UIFontDescriptorTraitItalic];
            targetFont = [UIFont fontWithDescriptor:fontD size:0];
        } else if(isItalic) {
            UIFontDescriptor *fontD = [font.fontDescriptor fontDescriptorWithSymbolicTraits:UIFontDescriptorTraitBold ];
            targetFont = [UIFont fontWithDescriptor:fontD size:0];
        }
            [string addAttribute:NSFontAttributeName value:targetFont range:range];
    }];
    
    [string addAttribute:NSParagraphStyleAttributeName value:pStyle range:NSMakeRange(0, string.length)];
    [string endEditing];
    return string;
}

Usage.m

NSString *htmlString = @"Hello <b>World</b>";
NSFont *myFont = [UIFont fontWithName:@"Arial" size:14.0f];

NSAttributedMutableString *string = [self htmlToAttributed:htmlString font:myFont paragraphSpacing:15.0f];