Re: Quick quest - C# Discussion Boards

Re: ToString() method on objects returned from a webservice (Compact framework)

30-Jun-09 4:43

Hi.
I'm having a problem and cannot find the solution. trust me, i've read lots on msdn and google'd, in the wrong places obviously but i hope someone here can help me.

I'm porting an application to compact framework 3 and to reduce client side load i created a webservice for the BL (also, else i would have to copy all code and compile to CF since i cant use "regular" dll's in CF)
this webservice exposes some custom classes and a couple of methods. a simple example would be

(in webservice)
public enum ToStringType {
FirstName,
LastName
}

public class person
{
public string firstname {get;set;}
public string lastname {get;set;}
public ToStringType stringtype {get;set;}
public person(){
stringtype = ToStringType.FirstName ;
}

public override ToString(){

public override string ToString()
{
string tostr = string.Empty;
switch (stringtype )
{
case ToStringType.FirstName :
tostr = FirstName;
break;
case ToStringType.LastName:
tostr = LastName;
break;

}
return tostr;
}

and the ws has a method returning person[]

on the client. when i run the method and get a list of persons
first of all:
myperson.ToString() returns the object class name. not first/last-name

so i add a method:
tostr (){
...
}
with the logic in tostring(),

this works. returns firstname. but
if i (on the client) myperson.stringtype =ToStringType.LastName;
and debug the application, i see that myperson.stringtype IS ToStringType.LastName
but the method returns firstname.
i would really get the tostring to work since i'm adding the person[] to a combobox and i prefer not to use datasource/bindings. (tried those to. same problem, Displaymember has no effect)

how come this split personality disorder in my classes, and why does ToString return the class name instead of my overloaded ToString method?

I hope someone can help me
regards Tomas

There is no spoon

modified on Tuesday, June 30, 2009 10:54 AM

SeMartens30-Jun-09 4:52

SeMartens

30-Jun-09 4:52

Why didn't you make lastName public like firstName?

It's not a bug, it's a feature!

Check out my CodeProject article Permission-by-aspect.

Me in Softwareland.

Re: ToString() method on objects returned from a webservice (Compact framework)

c0ax_lx30-Jun-09 4:57

Re: ToString() method on objects returned from a webservice (Compact framework)

30-Jun-09 4:57

Edited, Thanks for noticing! allthough this was just an example and not the actual code, else the post would have been very very long

If it' stuck, DO NOT pull harder!

SeMartens30-Jun-09 5:08

SeMartens

30-Jun-09 5:08

Maybe the StringType is not serialized correctly. I think you have to think about, how to serialise this type...

It's not a bug, it's a feature!

Check out my CodeProject article Permission-by-aspect.

Me in Softwareland.

Re: ToString() method on objects returned from a webservice (Compact framework)

c0ax_lx30-Jun-09 23:14

30-Jun-09 23:14

I tried changing StringType to int. did nothing. This confuses me a little.
The properties of the object can be modified and keeps their state on the client. but all changes
are lost on the server. since it is stateless one would think that the "original" values also
would be lost, and why isnt the client object values passed to the server for method invocation.
thank god for Apress Books and vacation coming up Smile | :)

Anyway, i solved this by having a local class with the same properties and my custom ToString.

If it' stuck, DO NOT pull harder!

Quick quest

gwithey30-Jun-09 4:29

30-Jun-09 4:29

Just wondering as rxMessage is looking at the 3rd byte not the second am I right putting :

switch (rxMessage[2])
{
case 0x56: // "V" Version Number Request
if (rxMessage.Length == 3)
{
rxCommmandType = commandType.VersionNumRequest;
}
else
{
throw new IndexOutOfRangeException("Inavlid data entered, "
+ "Incorect number of bytes for a display update");
}
break;

musefan30-Jun-09 4:35

30-Jun-09 4:35

I don't quite know what you are trying to do but one thing that stands out is you are checking to see if the array length is big enough after you access the data. If you want to check if it is available to access then do it before the switch.

Life goes very fast. Tomorrow, today is already yesterday.

gwithey30-Jun-09 4:44

30-Jun-09 4:44

Ah im just using it to check that i have recieved the correct number of bytes.

If there are more than three bytes in the recieved array then something is wrong throwing an exception.
In other words checking nothing follows the Version number request

c0ax_lx30-Jun-09 4:45

30-Jun-09 4:45

switch (rxMessage[2]) <- change to rxMessage[1] since arrays starts at 0.
rgds Tomas

If it' stuck, DO NOT pull harder!

gwithey30-Jun-09 4:48

30-Jun-09 4:48

byte 0 and one are filled i didnt add this code because it would have crowded the message
<code> // COMMAND HEADER
if (rxMessage[0] != (byte)'J')
{
throw new InvalidDataException("Error: Invalid Command Header found");
}

// MCU TYPE
if (rxMessage[1] != (byte)DEVICE_ID)
{
throw new InvalidDataException("Error: Invalid Device ID");
}

c0ax_lx30-Jun-09 4:54

30-Jun-09 4:54

Ok. i cant say i really understand your question, but rxMessage[2] is the 3'rd byte if that's what you're asking. MCU's are cool btw. i use AVR's alot Smile | :)

If it' stuck, DO NOT pull harder!

gwithey30-Jun-09 4:58

30-Jun-09 4:58

thats kwl thanx. The question was just to check that if i was in array[2] it would be containing three values.

So array.length should equal three or it is invalid so sure its right

musefan30-Jun-09 5:14

Filter GridView using a dropdown list but only after page populates with appropriate data from Query String

30-Jun-09 5:14

just because you are accessing index 2 of the array it does not mean the length is three. If you can access index 2 without an array then there are at least 3 values.

what you should do is first check the length...

if(array.Length != 3)
  //not correct version request message

then do your switch... I assume that index 3 tells what type of request it is and should always be present?

Life goes very fast. Tomorrow, today is already yesterday.

mjc22530-Jun-09 4:23

mjc225

30-Jun-09 4:23

I am using a GridView on a page that will need to display data based on either a URL passed in with a QueryString OR fields passed from a form. This may return 50-500 records or so based on the state etc... If this is too many, (and only if this is too many) the user will be able to filter based on the occupation. I can get it to filter on query string AND state at the same time but not or sadly. I want it to default to all occupations after pulling from the DB based on state, (I tried setting the default value for occupation to -1) and then, the user can use the dropdown control to filter it more.

<asp:dropdownlist id="ddlCategories" runat="server" appenddatabounditems="True" autopostback="True"
		datasourceid="sdsCategories" datatextfield="Occupation" datavaluefield="Occupation">
			<asp:listitem text="All Categories" value="-1">
		</asp:listitem>
	</asp:dropdownlist>
	<asp:sqldatasource id="sdsCategories" runat="server" connectionstring="<%$ ConnectionStrings:eventsConnectionString1 %>"
		selectcommand="SELECT [Occupation] FROM [Events]" ProviderName="<%$ ConnectionStrings:eventsConnectionString1.ProviderName %>">
	</asp:sqldatasource>


	<asp:gridview id="gvProducts" runat="server" datasourceid="sdsProducts" style="margin-top: 12px;" AllowSorting="True" AutoGenerateColumns="False">
		<columns>
            <asp:BoundField DataField="EventTitle" HeaderText="EventTitle" SortExpression="EventTitle" />
            <asp:BoundField DataField="EventEndDate" HeaderText="EventEndDate" SortExpression="EventEndDate" DataFormatString="{0:MM/dd/yyyy}" />
            <asp:BoundField DataField="EventStartDate" HeaderText="EventStartDate" SortExpression="EventStartDate" DataFormatString="{0:MM/dd/yyyy}" />
            <asp:BoundField DataField="EventCity" HeaderText="EventCity" SortExpression="EventCity" />
            <asp:BoundField DataField="EventState" HeaderText="EventState" SortExpression="EventState" />
            <asp:BoundField DataField="Occupation" HeaderText="Occupation" SortExpression="Occupation" />
		</columns>
	</asp:gridview>
	<asp:sqldatasource id="sdsProducts" runat="server" connectionstring="<%$ ConnectionStrings:eventsConnectionString2 %>"
		selectcommand="SELECT [EventTitle], [EventEndDate], [EventStartDate], [EventCity], [EventState], [Occupation] FROM [Events] WHERE ([EventState] = ?)" ProviderName="<%$ ConnectionStrings:eventsConnectionString2.ProviderName %>">
        <SelectParameters>
            <asp:QueryStringParameter DefaultValue="PA" Name="EventState" QueryStringField="ID"
                Type="String" />
        </SelectParameters>
	</asp:sqldatasource>

complete removing of a C# COM component

manustone30-Jun-09 3:24

manustone

30-Jun-09 3:24

Hi all
maybe you can help me a little bit with COM component developed in C#.

I created one C# COM component to provide Excel with some functionality I needeed.

Everything was fine until I did some change to the assembly.
In the new version I did the following:
-I used the same GUID of the old version
-I used using the same strong key name of the old version
- I changed the Assembly version to 1.0.0.0 to 1.0.0.1.
- I registered the assebly in the global assembly cache with gacutil.

Since then Excel is not able to work anymore with this Com and doesn't recognize the library classes.

I tryed to cleanup of my system so I did:
-removal of the library from the GAC
-removal of the typelib
-reinstall of everything from scratch

at the end nothing improved! Frown | :(

What can I do to a perfect clean up of my system?
Some tool or some registry key or value to see?

Thanks in advance
ManuStone

Combobox and listbox control

Hum Dum30-Jun-09 3:08

Hum Dum

30-Jun-09 3:08

On form load event i am loading dt Datatable obj from DB.

Setting Listbox control dataSource to dt, and respective display member, value member property. But its taking almost 2 sec,

If i do same for combobox control it takes hardly .1 sec

Why this behavior?

Re: Combobox and listbox control

musefan30-Jun-09 3:19

Re: Combobox and listbox control

30-Jun-09 3:19

well it might help to see the code you have used for both methods.

Life goes very fast. Tomorrow, today is already yesterday.

Hum Dum1-Jul-09 0:04

Hum Dum

1-Jul-09 0:04

musefan wrote:
well it might help to see the code you have used for both method

for combobox

Datatable dt = getTable();
cmb.DataSource = dt;
cmb.DisplayMember = "Name";
cmb.ValueMember = "Level";

for listbox

Datatable dt = getTable();
lst.DataSource = dt;
lst.DisplayMember = "Name";
lst.ValueMember = "Level";

On formLoad event.

this code i used, for cmb its fast, but for listbox its slow,
I am wondering why.........?? Confused | :confused:

i am using c#. vs2003

regards,

Re: Combobox and listbox control

musefan1-Jul-09 1:18