可以将C＃变量传递给PHP脚本吗？

I want to add a STRING inputted by the user in the C# program to a .PHP script, so that the .PHP script can use this user input. Is this possible?

While searching for this I keep finding POST threads. I do not want to POST to a database, I want to pass a C# STRING(username) to a PHP script(Logincheck.php).

My PHP script is handling the variable $inputusername exactly how I want it to but I can't seem to pass the C# STRING(username) to the $inputusername.