VB.net manage opened excel file on the fly -

in current project, need modify excel file opened. mean, need see change in excel file whenever modify it.

since opened file locked , vb cannot access file, solution open excel file, modify content , copy original file using excel vba, excel vba can used copy data between opening sheets.

here vb code in other excel file (called ttht.xlsm):

private sub worksheet_change(byval target range)   application.screenupdating = false   if sheet1.[b5].value = "#"   application.displayalerts = false   workbooks.open(thisworkbook.path & "\pcn.xlsm")     thisworkbook.sheets("ttht").[b5]         .parent.range("b4").copy         sheets("pcn").[b4].pastespecial 7         end     end application.displayalerts = true  end if end sub 

runs fine between 2 opening excel file ( ttht 1 , pcn.xlsm ).

now need do, fill data ttht, , put "#" b5 code. think work, it's not..

private sub btnupdate_click(sender system.object, e system.eventargs) handles btnupdate.click     dim oexcel object     dim obook object     dim osheet object     oexcel = createobject("excel.application")     oexcel.displayalerts = false     obook = oexcel.workbooks.open(tthtpath)     osheet = obook.worksheets("ttht")     osheet.range("b4").value = txtvalue_needed.text     osheet.range("b5").value = "#"     obook.save()     'system.diagnostics.process.start(duongdanphieucongnghe)     osheet = nothing     obook.close()     obook = nothing     oexcel.quit()     oexcel = nothing end sub 

result is, if open pcn file , click button, won't change. if close pcn , click button, change.. need see change on fly, not close , reopen each time need update. can shed me light, how, or function ... either vba or vb.net, should use ?

if file opened , has focus can try looking in running objects table.

dim excelapplication excel.application     excelapplication = getobject("c:\folder\excelworkbook.xls") 

then can make modifications on instance referenced while trying avoid disrupting user.

the getobject() function great; here's link. https://msdn.microsoft.com/en-us/library/e9waz863(v=vs.71).aspx