I have an enum:
public enum baseKey : uint
{
HKEY_CLASSES_ROOT = 0x80000000,
HKEY_CURRENT_USER = 0x80000001,
HKEY_LOCAL_MACHINE = 0x80000002,
HKEY_USERS = 0x80000003,
HKEY_CURRENT_CONFIG = 0x80000005
}
How can I, given the string HKEY_LOCAL_MACHINE, get a value 0x80000002 based on the enum?
baseKey choice;
if (Enum.TryParse("HKEY_LOCAL_MACHINE", out choice)) {
uint value = (uint)choice;
// `value` is what you're looking for
} else { /* error: the string was not an enum member */ }
Before .NET 4.5, you had to do the following, which is more error-prone and throws an exception when an invalid string is passed:
(uint)Enum.Parse(typeof(baseKey), "HKEY_LOCAL_MACHINE")
Using Enum.TryParse you don't need the Exception handling:
baseKey e;
if ( Enum.TryParse(s, out e) )
{
...
}
var value = (uint) Enum.Parse(typeof(baseKey), "HKEY_LOCAL_MACHINE");
With some error handling...
uint key = 0;
string s = "HKEY_LOCAL_MACHINE";
try
{
key = (uint)Enum.Parse(typeof(baseKey), s);
}
catch(ArgumentException)
{
//unknown string or s is null
}
var value = (uint)Enum.Parse(typeof(basekey), "HKEY_LOCAL_MACHINE", true);
This code snippet illustrates obtaining an enum value from a string. To convert from a string, you need to use the static Enum.Parse() method, which takes 3 parameters. The first is the type of enum you want to consider. The syntax is the keyword typeof() followed by the name of the enum class in brackets. The second parameter is the string to be converted, and the third parameter is a bool indicating whether you should ignore case while doing the conversion.
Finally, note that Enum.Parse() actually returns an object reference, that means you need to explicitly convert this to the required enum type(string,int etc).
Thank you.
Alternate solution can be:
baseKey hKeyLocalMachine = baseKey.HKEY_LOCAL_MACHINE;
uint value = (uint)hKeyLocalMachine;
Or just:
uint value = (uint)baseKey.HKEY_LOCAL_MACHINE;
"HKEY_LOCAL_MACHINE" to the value, as the OP asked, you converted the symbol HKEY_LOCAL_MACHINE to the value. Wildly different beasts.