interop - check if a sheet exists in excel -

how check if sheet exists in excel using interop. tried following throws comexception if not there.. there better way of finding out looking @ exception

    worksheet sheet = null;     sheets worksheets = some;      sheet = (worksheet)worksheets.get_item("sheetname");     if(sheet!=null) { //do } 

edit:

thanks input guys.

i wrote function

private dictionary<string, worksheet> getsheetsmap(sheets worksheets) {      if (worksheets == null)         throw new argumentnullexception("worksheets");       dictionary<string, worksheet> map = new dictionary<string, worksheet>(stringcomparer.currentcultureignorecase);     foreach (worksheet s in worksheets)     {         map.add(s.name, s);     }      return map; } 

and use below

 dictionary<string, worksheet> sheetmap = getsheetsmap(worksheets);             worksheet sheet = null;               if (sheetmap.trygetvalue(extendedtemplatemanager.basicusertemplate, out sheet))             {                 //found it.             } else { // not } 

do have workbook object? if so, can iterate on workbook.sheets array , check name property of each sheet.

foreach (sheet sheet in workbook.sheets) {     if (sheet.name.equals("sheetname"))     {         //do     } }