How to send mail with binary word in mail subject using PHP

Please refer RFC 2047 for detail format.

For simple, if your mail subject contains binary, and I use UTF-8 as a example:
$subject = '=?UTF-8?B?'.base64_encode($subject).'?=';

Linq Group By 2 columns

from c in db.Customers

group c by new { c.Country, c.City } into g

select new { g.Key.Country, g.Key.City, Count = g.Count() };

Left join in LINQ

In SQL:
SELECT * FROM table_A LEFT JOIN table_B WHERE table_A.col=table_B.col

In LINQ:
from a in table_A
join b in table_B on a.col equals b.col into temp
from finalSet in temp.DefaultIfEmpty()


hightlighted is the keywords that using left join in linq
seems using a temp dataset the set the record and fill the missing part in table_B with empty to get the finalSet.

How to remove duplicated 2-dimension array in PHP?

My sample array Data:

$arr[] = array(0,1,2,3);
$arr[] = array(4,5,2,1);
$arr[] = array(0,0,0,0);
$arr[] = array(0,1,2,3);

I expected to return

array(array(0,1,2,3), array(4,5,2,1), array(0,0,0,0));

Solution:
$arr = array_map('unserialize', array_unique(array_map('serialize', $arr)));

When to prefer JSON over XML?

Favor XML over JSON when any of these is true:

• You need message validation
• You're using XSLT
• Your messages include a lot of marked-up text
• You need to interoperate with environments that don't support JSON

Favor JSON over XML when all of these are true:

• Messages don't need to be validated, or validating their deserialization is simple
• You're not transforming messages, or transforming their deserialization is simple
• Your messages are mostly data, not marked-up text
• The messaging endpoints have good JSON tools