How to know what is the current company from the code using X++ in AX 2009?

 when you write any method sometimes you need to know what is the current company to check some data related to the company to do this see this example :

protected void test()
{
     CompanyInfo _CI;
    ;
 
if(_CI.company()=='sdx' )
{
 // write your code here
 }
}