Generic enum
Parser
There are many ways to parse an
enum
. For example, we could use
switch
in C# to parse
enum
. But the problem will be if that
enum
has 10 items in it (for example), then we need to write 10
case
statements. So if we have 10
enums
with 10 items, then we need to write 10x10
case
statements plus all the
deafult
statements.
I use the following technique to parse
enum
. First of all, I use the following two
enums
to describe this tip:
public enum EnumOne
{
None = 0,
One = 1,
Two = 2,
Three = 3
}
public enum EnumTwo
{
None,
One,
Two,
Three
}
So we could parse the above
enum
using the following
switch
code block,
public EnumOne ParseEnum(string item)
{
switch (item)
{
case "One":
return EnumOne.One;
case "Two":
return EnumOne.Two;
case "Three":
return EnumOne.Three;
}
return EnumOne.None;
}
But we want to parse
EnumOne
and
EnumTwo
. As a result, we need to write two blocks of
switch
, whereas the following generic
enum
parser will do the job using minimum lines of
code
.
public TEnum ParseEnum<TEnum>(string item, bool ignorecase = default(bool))
where TEnum : struct
{
TEnum tenumResult = default(TEnum);
return Enum.TryParse<TEnum>(item, ignorecase, out tenumResult) ?
tenumResult : default(TEnum);
}
To test the above code, we could use the following code block:
public void Test()
{
Console.WriteLine("{0}, {1}, {2}, {3}, {4}",
new object[]
{
ParseEnum("One"),
ParseEnum<EnumOne>("Two"),
ParseEnum<EnumTwo>("TwoTwo"),
ParseEnum<EnumTwo>("1"),
ParseEnum<EnumTwo>(string.Empty)
});
}
In this tip, we assume that whatever
enum
we are going to parse, it has a default value for example, in here
None is default for
EnumOne
and
EnumTwo
, otherwise parser will
return
first item of the
enum
.