https

1,/https安全认证

//    [manager.requestSerializer setAuthorizationHeaderFieldWithUsername:@"'" password:@""];

//    [manager.securityPolicy setAllowInvalidCertificates:YES];

2,base64

 NSData *decodeData = [str2 dataUsingEncoding:NSUTF8StringEncoding];

    NSString *base64Decode = [decodeData base64EncodedStringWithOptions:0];

//URL有中文

3, NSString *URLstr = [URl stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];