Hi i want to know how many lines of data there are in a regedit key of the user for example
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SystemInformation\ComputerHardwareIds
In my case i have 10 lines of GUID's in there, so how do i do this in c#?
From that link Registry Data Types (exists next to value name in registry)
REG_SZ Null-terminated string. It will be a Unicode or ANSI string, depending on whether you use the Unicode or ANSI functions.
REG_MULTI_SZ Array of null-terminated strings that are terminated by two null characters.
Depending on that answer just edited it a bit to match your request.
using (RegistryKey key = Registry.LocalMachine.OpenSubKey(@"SYSTEM\CurrentControlSet\Control\SystemInformation")) { if (key != null) { object value = key.GetValue("ComputerHardwareIds"); if (value != null) { var computerHardwareIds = (value as string[]); // cast value object to string array, because its type is REG_MULTI_SZ var lines_num = computerHardwareIds.Length; // then you can get lines number this way } } } 