.NET (Core and Framework)

'class variable
Private objMyLock As Object = New Object()

Public Sub LogSafe()
   SyncLock objMyLock
      'Do your logging here
      'Once one thread has passed SyncLock all next threads
      'will stop there until this thread has exited the block.
   End SyncLock
End Sub

void Form1::SOCR_Click(System::Object^  sender, System::EventArgs^  e)<br />
{<br />
	int i,j,k;<br />
	String^ fName = "Citi.tif";<br />
	MODI::Document^ doc = gcnew MODI::DocumentClass();	<br />
	doc->Create(fName);<br />
	doc->OCR(MODI::MiLANGUAGES::miLANG_SYSDEFAULT,true,true);<br />
<br />
	for(i=0; i < doc->Images->Count; i++)<br />
	{<br />
	MODI::Image^ img =(MODI::Image) doc->Images[i];// Error will be thrown on this line <br />
	}<br />
	<br />
}