stringByAddingPercentEscapesUsingEncoding(只對 `#%^{}[]|\"<> 加空格共14個字元編碼，不包括”&?”等符號), ios9將淘汰，建議用 stringByAddingPercentEncodingWithAllowedCharacters 方法 ...
stringByAddingPercentEscapesUsingEncoding(只對 `#%^{}[]|\"<> 加空格共14個字元編碼，不包括”&?”等符號), ios9將淘汰，建議用 stringByAddingPercentEncodingWithAllowedCharacters 方法
stringByAddingPercentEncodingWithAllowedCharacters 需要傳一個 NSCharacterSet 對象（關於 NSCharacterSet 這篇 文章說的很好）
如[NSCharacterSet URLQueryAllowedCharacterSet]
URLFragmentAllowedCharacterSet "#%<>[\]^`{|} URLHostAllowedCharacterSet "#%/<>?@\^`{|} URLPasswordAllowedCharacterSet "#%/:<>?@[\]^`{|} URLPathAllowedCharacterSet "#%;<>?[\]^`{|} URLQueryAllowedCharacterSet "#%<>[\]^`{|} URLUserAllowedCharacterSet "#%/:<>?@[\]^`
（2）網路訪問請求：中文空格字元解碼
stringByRemovingPercentEncoding ---- xcode7可能會提示要將stringByAddingPercentEscapesUsingEncoding替換成此方法，要根據是否是解碼來區分
代替 stringByAddingPercentEscapesUsingEncoding
let customAllowedSet = NSCharacterSet(charactersInString:"`#%^{}\"[]|\\<> ").invertedSet NSString *urlStr = [urlStr stringByAddingPercentEncodingWithAllowedCharacters:[[NSCharacterSet characterSetWithCharactersInString:@"?!@#$^&%*+,:;='\"`<>()[]{}/\\| "] invertedSet]];
