如何在HTML属性值的URL中编码"&"？

Question

我想在电子邮件应用中点击一下URL.问题是参数化的URL会因为URL中的"&"而破坏它.下面的body变量是问题行.两种版本的"身体"都是不正确的.电子邮件应用程序打开后,文本将停在"... link:"处.对&符号进行编码需要什么？

NSString *subject = @"This is a test";
NSString *encodedSubject = 
[subject stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; 

//NSString *body = @"This is a link: <a href='http://somewhere.com/two.woa/wa?id=000&param=0'>click me</a>"; //original
NSString *body = @"This is a link: <a href='http://somewhere.com/two.woa/wa?id=000&#38;param=0'>click me</a>"; //have also tried &amp;
NSString *encodedBody = 
[body stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; 
NSString *formattedURL = [NSString stringWithFormat: @"mailto:myname@somedomain.com?subject=%@&body=%@", encodedSubject, encodedBody];
NSURL *url = [[NSURL alloc] initWithString:formattedURL];
[[UIApplication sharedApplication] openURL:url];

Answer 1

对于URL编码标准中的HEX,&符号为%26

Answer 2

我一直在使用-[NSString gtm_stringByEscapingForURLArgument],它在Google Toolbox for Mac中提供,特别是在GTMNSString + URLArguments.h和GTMNSString + URLArguments.m中.