Simple code sample wanted: enum as method parameter

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Guest

I'm new to VS.NET, C#, and the enumerated datatype. I'm told that VS.NET
2005 Intellisense will pop up the members of an enum as a selection list if
you are using the enum as a method parameter. This sounds very handy.

I would really appreciate it if someone could give me a basic C# code sample
showing how this would be set up, both the enum and the method.

So let's say you're building a method, "ReturnPageType(...)", and you want
an enumerated list of possibilities to be displayed in Intellisense: "html"
"pdf" "mht".

What would the skeletal code be? I've tried a bunch of things, but it isn't
working, and for some reason I can't find a sample in literature on- or
offline.

Thank you,
-KF
 
I'm new to VS.NET, C#, and the enumerated datatype. I'm told that VS.NET
2005 Intellisense will pop up the members of an enum as a selection list if
you are using the enum as a method parameter. This sounds very handy.

I would really appreciate it if someone could give me a basic C# code sample
showing how this would be set up, both the enum and the method.

So let's say you're building a method, "ReturnPageType(...)", and you want
an enumerated list of possibilities to be displayed in Intellisense: "html"
"pdf" "mht".

What would the skeletal code be? I've tried a bunch of things, but it isn't
working, and for some reason I can't find a sample in literature on- or
offline.
Click to expand...

Copy this into a console app:

using System;

enum Foo
{
FirstValue,
SecondValue,
ThirdValue
}

class Program
{
static void Main(string[] args)
{
DoSomething
}

static void DoSomething(Foo foo)
{
}
}

and put your cursor just after DoSomething. Hit '(' and you'll be
presented with intellisense which suggests "Foo". Hit '.' and it'll
fill in Foo for you, and present you with FirstValue, SecondValue,
ThirdValue.
 
Thanks for the help Jon. I'm going to expose an abundance of ignorance,
here, but this is how we learn...

Following your skeleton code below as a template, I was able to make the
following code work just fine when I declared a static method. My
understanding of static methods is that they can be invoked without
instantiating an object, and Intellisense's behavior on the code below
seemed to work great
:
enum PageReturnType
{
txt,
html,
pdf,
mht
}

public class Scraper
{

static void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
//whatever
}

public void MyTest()
{
Scraper.ArchiveRemotePageAsPDF(PageReturnType.
}

As I said, this worked fine. When I try to make my code so that it can work
against object instances, using public methods rather than static, I no
longer get a method list:

enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
myScraper = new Scraper;
Scraper.
Scraper.ArchiveRemotePageAsPDF(PageReturnType.mht);

}
}

I'm doing something dumb and missing something fundamental. What is it?

Thanks,
-KF


Jon Skeet said:
I'm new to VS.NET, C#, and the enumerated datatype. I'm told that VS.NET
2005 Intellisense will pop up the members of an enum as a selection list
if
you are using the enum as a method parameter. This sounds very handy.

I would really appreciate it if someone could give me a basic C# code
sample
showing how this would be set up, both the enum and the method.

So let's say you're building a method, "ReturnPageType(...)", and you
want
an enumerated list of possibilities to be displayed in Intellisense:
"html"
"pdf" "mht".

What would the skeletal code be? I've tried a bunch of things, but it
isn't
working, and for some reason I can't find a sample in literature on- or
offline.
Click to expand...

Copy this into a console app:

using System;

enum Foo
{
FirstValue,
SecondValue,
ThirdValue
}

class Program
{
static void Main(string[] args)
{
DoSomething
}

static void DoSomething(Foo foo)
{
}
}

and put your cursor just after DoSomething. Hit '(' and you'll be
presented with intellisense which suggests "Foo". Hit '.' and it'll
fill in Foo for you, and present you with FirstValue, SecondValue,
ThirdValue.
Click to expand...
 
Hi Kefine,
the difference between a static and non static method is that the static
method does not belong to a single instance of a class it belongs at the
class level, meaning if you have a class called MyClass then you could call a
static method by saying:

MyClass.MyStaticMethod();

if the method is not static then you have to call the method on a specific
instance of the type like:

MyClass objX = new MyClass();
objX.MyNonStaticMethod();


So in your code you will have to change:

enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
myScraper = new Scraper;
Scraper.
Scraper.ArchiveRemotePageAsPDF(PageReturnType.mht);

}
}



into:




enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
//create an object instance of type Scraper
Scraper myScraper = new Scraper();

//on the specific instance you can now call the method because it
//is no longer static you can not reference it at a class level
myScraper.ArchiveRemotePageAsPDF(PageReturnType.mht);
}
}


[email protected] said:
Thanks for the help Jon. I'm going to expose an abundance of ignorance,
here, but this is how we learn...

Following your skeleton code below as a template, I was able to make the
following code work just fine when I declared a static method. My
understanding of static methods is that they can be invoked without
instantiating an object, and Intellisense's behavior on the code below
seemed to work great
:
enum PageReturnType
{
txt,
html,
pdf,
mht
}

public class Scraper
{

static void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
//whatever
}

public void MyTest()
{
Scraper.ArchiveRemotePageAsPDF(PageReturnType.
}

As I said, this worked fine. When I try to make my code so that it can work
against object instances, using public methods rather than static, I no
longer get a method list:

enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
myScraper = new Scraper;
Scraper.
Scraper.ArchiveRemotePageAsPDF(PageReturnType.mht);

}
}

I'm doing something dumb and missing something fundamental. What is it?

Thanks,
-KF


Jon Skeet said:
I'm new to VS.NET, C#, and the enumerated datatype. I'm told that VS.NET
2005 Intellisense will pop up the members of an enum as a selection list
if
you are using the enum as a method parameter. This sounds very handy.

I would really appreciate it if someone could give me a basic C# code
sample
showing how this would be set up, both the enum and the method.

So let's say you're building a method, "ReturnPageType(...)", and you
want
an enumerated list of possibilities to be displayed in Intellisense:
"html"
"pdf" "mht".

What would the skeletal code be? I've tried a bunch of things, but it
isn't
working, and for some reason I can't find a sample in literature on- or
offline.
Click to expand...

Copy this into a console app:

using System;

enum Foo
{
FirstValue,
SecondValue,
ThirdValue
}

class Program
{
static void Main(string[] args)
{
DoSomething
}

static void DoSomething(Foo foo)
{
}
}

and put your cursor just after DoSomething. Hit '(' and you'll be
presented with intellisense which suggests "Foo". Hit '.' and it'll
fill in Foo for you, and present you with FirstValue, SecondValue,
ThirdValue.
Click to expand...
Click to expand...
 
Super, thanks, uber Bene. Many thanks to you Mark and to Jon as well. Much
appreciated.

-KF

Mark R. Dawson said:
Hi Kefine,
the difference between a static and non static method is that the static
method does not belong to a single instance of a class it belongs at the
class level, meaning if you have a class called MyClass then you could
call a
static method by saying:

MyClass.MyStaticMethod();

if the method is not static then you have to call the method on a specific
instance of the type like:

MyClass objX = new MyClass();
objX.MyNonStaticMethod();


So in your code you will have to change:

enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
myScraper = new Scraper;
Scraper.
Scraper.ArchiveRemotePageAsPDF(PageReturnType.mht);

}
}



into:




enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
//create an object instance of type Scraper
Scraper myScraper = new Scraper();

//on the specific instance you can now call the method because it
//is no longer static you can not reference it at a class level
myScraper.ArchiveRemotePageAsPDF(PageReturnType.mht);
}
}


[email protected] said:
Thanks for the help Jon. I'm going to expose an abundance of ignorance,
here, but this is how we learn...

Following your skeleton code below as a template, I was able to make the
following code work just fine when I declared a static method. My
understanding of static methods is that they can be invoked without
instantiating an object, and Intellisense's behavior on the code below
seemed to work great
:
enum PageReturnType
{
txt,
html,
pdf,
mht
}

public class Scraper
{

static void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
//whatever
}

public void MyTest()
{
Scraper.ArchiveRemotePageAsPDF(PageReturnType.
}

As I said, this worked fine. When I try to make my code so that it can
work
against object instances, using public methods rather than static, I no
longer get a method list:

enum PageReturnType
{
txt,
html,
pdf,
mht
}
public class Scraper
{
public void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
}
public void MyTest()
{
myScraper = new Scraper;
Scraper.
Scraper.ArchiveRemotePageAsPDF(PageReturnType.mht);

}
}

I'm doing something dumb and missing something fundamental. What is it?

Thanks,
-KF


Jon Skeet said:
I'm new to VS.NET, C#, and the enumerated datatype. I'm told that
VS.NET
2005 Intellisense will pop up the members of an enum as a selection
list
if
you are using the enum as a method parameter. This sounds very handy.

I would really appreciate it if someone could give me a basic C# code
sample
showing how this would be set up, both the enum and the method.

So let's say you're building a method, "ReturnPageType(...)", and you
want
an enumerated list of possibilities to be displayed in Intellisense:
"html"
"pdf" "mht".

What would the skeletal code be? I've tried a bunch of things, but it
isn't
working, and for some reason I can't find a sample in literature on-
or
offline.

Copy this into a console app:

using System;

enum Foo
{
FirstValue,
SecondValue,
ThirdValue
}

class Program
{
static void Main(string[] args)
{
DoSomething
}

static void DoSomething(Foo foo)
{
}
}

and put your cursor just after DoSomething. Hit '(' and you'll be
presented with intellisense which suggests "Foo". Hit '.' and it'll
fill in Foo for you, and present you with FirstValue, SecondValue,
ThirdValue.
Click to expand...
Click to expand...
Click to expand...
 
Thanks for the help Jon. I'm going to expose an abundance of ignorance,
here, but this is how we learn...

Following your skeleton code below as a template, I was able to make the
following code work just fine when I declared a static method. My
understanding of static methods is that they can be invoked without
instantiating an object, and Intellisense's behavior on the code below
seemed to work great
:
enum PageReturnType
{
txt,
html,
pdf,
mht
}

public class Scraper
{

static void ArchiveRemotePageAsPDF(PageReturnType pagereturntype)
{
//whatever
}

public void MyTest()
{
Scraper.ArchiveRemotePageAsPDF(PageReturnType.
}

As I said, this worked fine. When I try to make my code so that it can work
against object instances, using public methods rather than static, I no
longer get a method list:
Click to expand...

<snip>

Well, you're trying to call an instance method (ArchiveRemotePageAsPDF)
as if it were a static method. Try

myScraper. (or this.)

instead of

Scraper.

and you should get a list.
 
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