Re: Get name of variable - C# Discussion Boards

Re: Using outlook to send messages.

9-May-04 2:23

If you're going to try to just put an email into a folder, you might as well use Outlook to send as well.

My suggestion is to just make that a system requirement: Outlook 2002 or above. Or, as I said, search this site for more information on MAPI. You can google, too.

The thing is that MAPI is pretty basic functionality and Microsoft has limited what MAPI can do (like enumerate the address book). They created Extended MAPI (EMAPI) to replace that functionality, but EMAPI does not expose any automation interfaces so that only early-binding languages can use it (C/C++ mainly) - so that script can't access it (and a COM interop library can't be created from it). You can encapsulate EMAPI using .NET, however, by P/Invoking the require methods and creating the IUnknown interfaces yourself. Several people have already done this, so you can use their implementation.

You could also check out Simple MAPI.NET[^] here on CodeProject. This implementation uses MAPI so there will be a security warning for Outlook XP and 2003 that tells the user a program is trying to access certain features, which they can allow or deny.

Encapsulating EMAPI is your best bet, and should work just fine for Outlook 2000 and newer. Anything older would probably be rare, running on a machine that can't run the .NET Framework anyway (i.e., Windows 95), or become too big of a burden and too costly to develop.

Microsoft MVP, Visual C#
My Articles

mpalle9-May-04 2:39

mpalle

9-May-04 2:39

Hi

Thanks very much for the info.
I'll try to give emapi a shot then.
I have tryed the simple mapi example here on the site and it works like a charm. But the problems keeps coming .. the simple mapi example dosnt support the option to add headers to the email like "Disposition-Notification-To". but ill have to settel then.
But once again thanks for the help

MTP

Get name of variable

Stefan Troschuetz8-May-04 4:06

8-May-04 4:06

Hi!

Is it possible to get the name of a variable as a string?
For the following example I want to get the string "variable".

<br />
class Test<br />
{<br />
private int variable;<br />
}<br />

I looked into Reflection namespace, but found nothing that fits well. The namespace provides class FieldInfo but unfortunately the only way to get an instance are the methods GetField or the GetFields. Both methods would more or less require that i already know the name of the variable.

THX in advance!

Hesham Amin8-May-04 4:13

Hesham Amin

8-May-04 4:13

I believe there is no way...
why do you need this ?

Stefan Troschuetz8-May-04 4:22

8-May-04 4:22

I'm storing some data of my class in a XML file that I read out later.

<br />
XmlTextWriter writer = new XmlTextWriter(this.configFilePath, this.configFileEncoding);<br />
writer.WriteStartDocument();<br />
writer.WriteStartElement("Configuration");<br />
writer.WriteElementString("Duration",		this.duration.ToString());<br />
writer.WriteEndElement();//Configuration<br />
writer.WriteEndDocument();<br />

Thought it would be nice to get the string for the localName param by determining the name of the variable instead of hardcoding it.

kayhustle8-May-04 16:03

kayhustle

8-May-04 16:03

You can get the name. Let's say you have a class Test as follows,

class Test<br />
{<br />
private int variable;<br />
private int Variable<br />
{<br />
get{return variable;}<br />
}<br />
private int VariableFunc()<br />
{<br />
return variable;<br />
}<br />
}

Let says we use the FindNames class to get the names of the members of this class. Since we already know the class name we can do,

using System.Reflection;<br />
class FindNames<br />
{<br />
<br />
	public string[] GetNamesType()<br />
	{<br />
		Type mytype = typeof(Test);<br />
		ArrayList names = new ArrayList();<br />
		PropertyInfo [] properties = mytype.GetProperties(BindingFlags.NonPublic|BindingFlags.Instance);<br />
		foreach(PropertyInfo pinfo in properties)<br />
		{<br />
			names.Add(pinfo.Name);//this will get the string "Variable"<br />
		}<br />
		FieldInfo [] fields= mytype.GetFields(BindingFlags.NonPublic|BindingFlags.Instance);<br />
		foreach(FieldInfo finfo in fields)<br />
		{<br />
			names.Add(finfo.Name);//this will get the string "variable"<br />
		}<br />
		MethodInfo [] methods = mytype.GetMethods(BindingFlags.NonPublic|BindingFlags.Instance|BindingFlags.DeclaredOnly);<br />
		foreach(MethodInfo methinfo in properties)<br />
		{<br />
			names.Add(methinfo.Name);//this will get the string "VariableFunc"<br />
		}<br />
		MemberInfo [] members = mytype.GetMembers<br />
			(BindingFlags.NonPublic|BindingFlags.Instance);<br />
		foreach(MemberInfo minfo in members)<br />
		{<br />
			names.Add(pinfo.Name);//this will get the strings "Variable", "variable",<br />
			//"VariableFunc",<br />
		}<br />
<br />
		return names.ToArray(typeof(string)) as string[];<br />
	}<br />

Make sure you put in the BindingFlags.Instance or BindingFlags.Static or it will throw an exception. Play around with the BindingFlags depending on what type of members you want to get. You can find out many useful things about the member of the class including its type, name, etc. You can also dynamically get/set/invoke it if it is static, or get/set/invoke it on an instance that you pass in. P.S. if you don't want to hardcode the class name too then you can just take an instance of that class and do something like
Type mytype=instance.GetType();
.
.
.
Hope that helped.

Stefan Troschuetz9-May-04 0:51

9-May-04 0:51

THX for your posting.
I knew I could make it this way and searched for an easier way. Furthermore, what do you do if the class has more than one field? Which element of the names ArrayList do you use?

<br />
FieldInfo [] fields= mytype.GetFields(BindingFlags.NonPublic|BindingFlags.Instance);<br />
foreach(FieldInfo finfo in fields)<br />
{<br />
names.Add(finfo.Name); <br />
}<br />

Heath Stewart8-May-04 19:29

8-May-04 19:29

Why don't you look into XML serialization? Read the documentatio for the classes in the System.Xml.Serialization namespace. The XmlSerializer already supports this and you can always override defauls using the attributes also in that namespace. Why do what's been already done for you in the .NET FCL?

Microsoft MVP, Visual C#
My Articles

Stefan Troschuetz9-May-04 0:42

9-May-04 0:42

THX for pointing me to this. I'm consistently astonished what else the .NET FCL has to offer. Smile | :)

But I think it doesn't fit right for what I'm trying to do as I also want to write comments and private fields to the XML file.
Anyway, I will keep the XmlSerializer in mind. Surely, I will need it sometimes.

Heath Stewart9-May-04 2:51

C# Questions relating to TextBox

9-May-04 2:51

To learn what the FCL has - browse through the class library documentation. You don't have to memorize everything, but at least understand what's there and were. As you develop .NET applications and libraries, you should also see a pattern that Microsoft uses to try to maintain consistency. Like for provider classes: you'll typically see a static Create or CreateInstance method.

If you want to serialize your class in such a way, then you'll have to do it yourself. But take a lesson from both XML and runtime serialization. A good solution would be to create a new attribute - say XmlCommentAttribute - that stores the comment for a field:

[AttributeUsage(AttributeTargets.Property | AttributeTargets.Field)]
public class XmlCommentAttribute : System.Attribute
{
  private string comment;
  public XmlCommentAttribute(string comment)
  {
    this.comment = comment;
  }
  public string Comment
  {
    get { return this.comment; }
  }
}

This would allow you to declaritivly define the comments for your fields:

[XmlRoot("myClass", Namespace="urn:myClass"]
public class MyClass
{
  [XmlComment("This is parsed as a string.")]private string field1;
  [XmlElement("myField2"), XmlComment("This is an int.")] private int field2;
  // ...
}

Noticed how I used the XML serialization attributes in places? This allows you to easily rename members or declare how things are stored, whether they should be elements or attributes, etc. If they aren't, you can have your serialization routine default to one or the other. Then just do something like this:

FieldInfo[] fields = myClass1.GetType().GetFields(
  BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);
foreach (FieldInfo field in fields)
{
  if (!field.IsNotSerialized) // At least honor the NotSerializedAttribute
  {
    string name = field.Name;
    bool useElement = true;
    string comment = null;
 
    // Get optional element name from custom attributes.
    XmlElementAttribute[] elemAttrs = (XmlElementAttribute[])
      field.GetCustomAttributes(typeof(XmlElementAttribute))
    if (elemAttrs != null && elemAttrs.Length > 0)
      name = elemAttrs[0].ElementName;
    else
    {
      // Get optional attribute name from custom attributes.
      XmlAttributeAttribute[] attrAttrs = (XmlAttributeAttribute[])
        field.GetCustomAttributes(typeof(XmlAttributeAttribute));
      if (attrAttrs != null && attrAttrs.Length > 0)
      {
        useElement = false;
        name = attrAttrs[0].AttributeName;
      }
    }
 
    // Get optional XML comment string.
    XmlCommentAttribute[] comments = (XmlCommentAttributes[])
      field.GetCustomAttributes(typeof(XmlAttributeAttributes));
    if (comments != null && comments.Length > 0)
      comment = comments[0].Comment;
 
    // Now write all this to your XmlTextWriter or whatever you use.
    // ...
  }
}

Basically, try to handle the basic XML elements so that you can easily override how fields are named. If you ever change private member names (not typically a good idea - always keep serialization in the back of your head when developing) you can use XML attributes to keep their serialized form the same - thus not breaking your new code against old serialized formats.

Finally, use FieldInfo to get the value. This is very easy to use. Do not just use ToString on the returned object (if it's not null). First, try to get the TypeConverter for the Type like so:

TypeConverter converter = TypeDescriptor.GetConverter(field.FieldType);

Use that to convert to and from strings. If you just use ToString, you'll have to handle the parsing yourself. Some types provide their own parsing, but typically only the primatives and the methods often use different signatures. You can also use the ConvertTo class, but those only cover the primatives. Using a TypeConverter makes your code more robust.

Microsoft MVP, Visual C#
My Articles

add a property

cristina_tudor8-May-04 2:48

cristina_tudor

8-May-04 2:48

What steps do I need to follow for adding a new property to an existing class?

Thanks for your help.
Best regards,

Cristina

Re: add a property

Dave Kreskowiak8-May-04 3:17

Dave Kreskowiak

8-May-04 3:17

You would have to write your own class, inheriting from the class you want to extend. Then you just supply your property code and the code that will use that property.

RageInTheMachine9532

Member 6910898-May-04 0:33

Member 691089

8-May-04 0:33

I'm a C# newbie. How can I insert a new line into a multi-line TextBox field? I've tried '\n' but instead of inserting a new line, it displays a strange character. Also, I want a particular method to execute when a user presses 'Enter' key after typing something in TextBox. Please help! Confused | :confused:

mughalali

Hesham Amin8-May-04 1:19

Hesham Amin

8-May-04 1:19

try "\r\n"

surgeproof8-May-04 4:21

surgeproof

8-May-04 4:21

if the other suggestion doesn't work, it may be something like or one of those sets. for the return, why not do a keypress event?

surgeproof

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kayhustle8-May-04 5:19

kayhustle

8-May-04 5:19

Use Environment.NewLine, which will guarantee the placement of a newline.

Heath Stewart8-May-04 19:56