Remove Excel application

[jslmvl]

Hi,

I did all my best to remove Excel:
book.Close(true,miss,miss);
excel.Workbooks.Close();
excel.Quit();
System.Runtime.InteropServices.Marshal.ReleaseComObject(excel);
excel = null;
but from the Windows Task Manager I can see EXCEL.EXE still there until I stoped the program. What I was missing?

Following is the full code:

private void button1_Click(object sender, EventArgs e)
{
Excel.Application excel = new Excel.Application();
Excel.Range range;
object miss = System.Reflection.Missing.Value;
//excel.Visible = true;
string fileName = Application.StartupPath + "\\Book1.xlsx";
Excel.Workbook book = excel.Workbooks.Open(fileName, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss);
Excel.Worksheet sheet = (Excel.Worksheet)book.Worksheets[1];
range = (Excel.Range)sheet.Cells[1, 1];
MessageBox.Show(range.Font.Name.ToString());
MessageBox.Show(range.Font.Size.ToString());
book.Close(true,miss,miss);
excel.Workbooks.Close();
excel.Quit();
System.Runtime.InteropServices.Marshal.ReleaseComObject(excel);
excel = null;
}

Thank you in advance.

 

[jmeckley]

if Excel.Application implements IDisposable (it will have a member named Dispose()) wrap the code in a using statement to manage the disposal.

using(var excel = new Excel.Application())
{
   Excel.Range range;
   object miss = System.Reflection.Missing.Value;
   var fileName = Application.StartupPath + "\\Book1.xlsx";
   Excel.Workbook book = excel.Workbooks.Open(fileName, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss, miss);
   Excel.Worksheet sheet = (Excel.Worksheet)book.Worksheets[1];
   range = (Excel.Range)sheet.Cells[1, 1];
   MessageBox.Show(range.Font.Name.ToString());
   MessageBox.Show(range.Font.Size.ToString());
   book.Close(true,miss,miss);
   excel.Workbooks.Close();
   excel.Quit();
}

Jason Meckley
Programmer
Specialty Bakers, Inc.

faq855-7190

 

[jslmvl]

Thanks a lot for your help!
Then, how to put those code into
private void button1_Click(object sender, EventArgs e)
{
}

 

[jmeckley]

copy and paste

Jason Meckley
Programmer
Specialty Bakers, Inc.

faq855-7190

 

[jslmvl]

Thak you.
I pasted and got
Error 1 'Microsoft.Office.Interop.Excel.Application': type used in a using statement must be implicitly convertible to 'System.IDisposable'
What I was missing?

 

[jmeckley]

if Excel.Application implements IDisposable ... wrap the code in a using statement to manage the disposal.

it doesn't implement IDisposable. how long are you waiting before checking the object is (un)marshalled? it may be that GC hasn't performed a cleanup.

If you are monitoring performance/memory usage I would also recommend dotTrace from JetBrains. this is a great tool to have for just these scenarios.

Jason Meckley
Programmer
Specialty Bakers, Inc.

faq855-7190

 

[jslmvl]

I think it is a basic job for C sharp to remove Excel since even VB can do this without difficulty...perhaps I was missing some thing very simple...

 

[MadJock]

Hi,

I've had this issue before with Excel Interop. The only solution (yes - not strictly best practice) is to do a GC.Collect().

Hope this helps,

Graeme


"Just beacuse you're paranoid, don't mean they're not after you