Identify and trapping specific error reading WinXPregistry values

[JohnJohnUSA]

I ran the following program to retrieve entries from the windows registry on Windows XP:

Program Code:

import win32api, win32con
aReg = win32api.RegConnectRegistry(None, win32con.HKEY_CURRENT_USER)
aKey = win32api.RegOpenKeyEx(aReg, r"Software\Microsoft\Internet Explorer\PageSetup")
for i in range(100):
Name, Data, Type = win32api.RegEnumValue(aKey, i)
print "Index=(", i,") Name=[", Name,"] Data=[",Data,"] Type=[",Type,"]"
win32api.RegCloseKey(aKey)

Program output:

Index=( 0 ) Name=[ header ] Data=[ &w&bPage &p of &P ] Type=[ 1 ]
Index=( 1 ) Name=[ footer ] Data=[ &u&b&d ] Type=[ 1 ]
Index=( 2 ) Name=[ margin_bottom ] Data=[ 0.750000 ] Type=[ 1 ]
Index=( 3 ) Name=[ margin_left ] Data=[ 0.750000 ] Type=[ 1 ]
Index=( 4 ) Name=[ margin_right ] Data=[ 0.750000 ] Type=[ 1 ]
Index=( 5 ) Name=[ margin_top ] Data=[ 0.750000 ] Type=[ 1 ]

Traceback (most recent call last):
File "F:/temp/Python Test Folder/Read Windows Registry Entries (No error trapping).py", line 5, in -toplevel-
Name, Data, Type = win32api.RegEnumValue(aKey, i)
error: (259, 'PyRegEnumValue', 'No more data is available.')


I received an error because I tried to read past the last entry for this key. The following is a modified version of the program to trap any error on key entry retrieval:

Program Code:

import win32api, win32con, sys
aReg = win32api.RegConnectRegistry(None, win32con.HKEY_CURRENT_USER)
aKey = win32api.RegOpenKeyEx(aReg, r"Software\Microsoft\Internet Explorer\PageSetup")
for i in range(100):
try:
Name, Data, Type = win32api.RegEnumValue(aKey, i)
print "Index=(", i,") Name=[", Name,"] Data=[",Data,"] Type=[",Type,"]"
except:
break
win32api.RegCloseKey(aKey)

Program output:

Code:
Index=( 0 ) Name=[ header ] Data=[ &w&bPage &p of &P ] Type=[ 1 ]
Index=( 1 ) Name=[ footer ] Data=[ &u&b&d ] Type=[ 1 ]
Index=( 2 ) Name=[ margin_bottom ] Data=[ 0.750000 ] Type=[ 1 ]
Index=( 3 ) Name=[ margin_left ] Data=[ 0.750000 ] Type=[ 1 ]
Index=( 4 ) Name=[ margin_right ] Data=[ 0.750000 ] Type=[ 1 ]
Index=( 5 ) Name=[ margin_top ] Data=[ 0.750000 ] Type=[ 1 ]

The latter program will trap any error resulting from trying to retrieve the key values. What I want to do is to specifically trap the error denoting that there is no more data available so I can continue executing more code as oppose to aborting the program. if the error is something other than no more data available, then I want to abort the program with an error message.

What code is needed to specifically trap the "no more data is available" error?

Thank you in advance for your help!

 

[EBGreen]

Try this:

import win32api, win32con, sys
aReg = win32api.RegConnectRegistry(None, win32con.HKEY_CURRENT_USER)
aKey = win32api.RegOpenKeyEx(aReg, r"Software\Microsoft\Internet Explorer\PageSetup")
for i in range(100):
try:
Name, Data, Type = win32api.RegEnumValue(aKey, i)
print "Index=(", i,") Name=[", Name,"] Data=[",Data,"] Type=[",Type,"]"
except:
cla, exc, trbk = sys.exc_info()
if exc.__dict__["args"][2] == "No more data is available.":
print "No more keys"
break
else:
print "Some other error"
break
win32api.RegCloseKey(aKey)

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