Encrypting XML **elements** - C# Discussion Boards

Jibesh6-Jan-13 22:33

Jibesh

6-Jan-13 22:33

what have your tried so far?

Jibesh V P

fatima...686-Jan-13 22:40

fatima...68

6-Jan-13 22:40

what your mean?

Jibesh6-Jan-13 22:44

Jibesh

6-Jan-13 22:44

have you started writing any code to implement this? if yes means where you stuck.

Jibesh V P

RLE encoding/decoding tool C#

Richard MacCutchan6-Jan-13 23:13

Richard MacCutchan

6-Jan-13 23:13

What are the inputs to your creation process and what structure do you expect at the end? You need to explain what sort of tree you are trying to create, and why you need to use recursion.

One of these days I'm going to think of a really clever signature.

Oleg Orlov6-Jan-13 16:15

Oleg Orlov

6-Jan-13 16:15

Hello World!

I've done my project: "RLE encoding/decoding tool" and have published source code at the CodePlex repository: http://rle.codeplex.com/

The source code is available here: http://rle.codeplex.com/SourceControl/changeset/view/c96568c408b1#rletoolv1.cs

I think, that you will be able to find the download package by yourself.

First of all, why do I create such discussion here: I want to listen to the well criticism for my source and what I must to fix/add at the future uploads.

Thank you,
Best Regards,
Oleg

Re: RLE encoding/decoding tool C#

Richard MacCutchan6-Jan-13 22:18

Richard MacCutchan

6-Jan-13 22:18

This is the wrong place, please post at Collaboration & Beta Testing[^].

One of these days I'm going to think of a really clever signature.

Re: RLE encoding/decoding tool C#

Oleg Orlov6-Jan-13 23:40

Oleg Orlov

6-Jan-13 23:40

Thank you!

Encrypting XML **elements**

SledgeHammer016-Jan-13 10:15

SledgeHammer01

6-Jan-13 10:15

I have a requirement to serialize out an object to XML where certain elements are encrypted for privacy / security reasons.

I've seen some samples on the internet for doing this, but they are all hardcoded. I.e. after the object is serialized you "patch" the elements you want to encrypt with the encrypted version. Not liking the hardcoded aspect of this solution. Also having to hardcode the decryption parts.

I've seen another solution where you use the XmlIgnore attribute on the plain text property and then add an "encrypted" version of the property and use the XML attributes to rename it. Not liking that you need 2 versions of every "secure" property.

Are there any other options? Ideally I would like something "in the spirit of .NET" along the lines of:

public class SomeObject
{
[XMLEncrypt]
public string SomeProp { get; set; }

public int SomeIntProp { get; set; }
}

where its something ".NETy" like a custom attribute or something like that. Unfortunately, I don't really see any way to hook into the XML serializer without completely re-writing it.

I thought about deriving a class from XMLSerializer and providing my own Serialize function that calls the base class and then afterwards goes through the object graph via reflection and patches the elements marked with the XMLEncrypt attribute, but I'm not really liking that idea that much either.

Any other suggestions?

Brisingr Aerowing6-Jan-13 14:12

Brisingr Aerowing

6-Jan-13 14:12

SharpSerializer[^]?

It's open source, so you can mod it to make it do what you want. It's a NewBSD License, so I think you can do pretty much anything you need with it.

Bob Dole
The internet is a great way to get on the net.

2.0.82.7292 SP6a

SledgeHammer017-Jan-13 6:32

SledgeHammer01

7-Jan-13 6:32

Hmm... don't really care for its dictionary style XML output (makes the files a lot bigger then they need to be) and couldn't find a quick way to turn that off, but I looked around for another open source serializer based on your suggestion and found YaxLib... gonna see if I can hook my encryption into that one.

BobJanova7-Jan-13 5:31

BobJanova

7-Jan-13 5:31

You're going to have to use reflection to find the encrypted properties in some way. That last suggestion of yours doesn't sound that bad to me. Deserialisation might be a pain in that case though.

SledgeHammer017-Jan-13 6:34

SledgeHammer01

7-Jan-13 6:34

I was thinking about this on the way into work this morning. You are right. The encrypted version is always going to be a string. Even if the underlying value is an int or something, so I'd have to find a way to store the temp string value before decrypting it to the real type. Currently looking into modding an open source serializer to support encryption "the right way".

Delete specific matching rows in datatable

Mustafa Kok8-Jan-13 23:46

Mustafa Kok

8-Jan-13 23:46

Binary formatter solves this by providing custom serialization option. It calls OnSerializing, OnSerialized, OnDeserializing and OnDeserialized methods. There may be a similar solution for XML Serializer, you may also try this.

Member 97041536-Jan-13 8:20

6-Jan-13 8:20

Could someone explain the best method for deleting all rows from a datatable where the value in column 0 is zero? I'm not sure how to handle the indexing after a row has been deleted...
Many thanks Thumbs Up | :thumbsup:

Wendelius6-Jan-13 8:30

6-Jan-13 8:30

One way is that you loop through the rows and test if the row satisfies with your condition. So something like:

foreach(System.Data.DataRow datarow in mydatatable.Rows) {
   if ((int)datarow["columnname"] == 0) {
      datarow.Delete();
   }
}
mydatatable.AcceptChanges();

For more information, see: DataRow.Delete Method[^]

The need to optimize rises from a bad design.My articles[^]

Member 97041536-Jan-13 9:36

6-Jan-13 9:36

Thanks for the response. I forgot to mention that my column's type is double. I tried your code and got an error, so I changed it to :-

foreach (System.Data.DataRow datarow in tblStanding.Rows)
{
    if ((double)datarow["Charge"] == 0)
    {
        datarow.Delete();
    }
}
tblStanding.AcceptChanges();

...and I get this error:-

"Collection was modified; enumeration operation might not execute."

Any ideas why?

Wendelius6-Jan-13 9:58

6-Jan-13 9:58

Sorry, my mistake. The safest way to loop through the rows when modifying them is to use the index. So try something like:

for (int counter = tblStanding.Rows.Count - 1; counter >= 0; counter--) {
    if ((double)tblStanding.Rows[counter]["Charge"] == 0)
    {
        tblStanding.Rows[counter].Delete();
    }
}
tblStanding.AcceptChanges();

The need to optimize rises from a bad design.My articles[^]

modified 6-Jan-13 16:31pm.

Member 97041536-Jan-13 10:13

6-Jan-13 10:13

I tried the code and got this message :-

The name 'datarow' does not exist in the current context"

So, I tried changing the code to:-

tblStanding.Rows[counter].Delete();

That ran, but the rows with zeros weren't deleted??

Edit - Strangely some of the rows with zeros were deleted, but some remain??

Wendelius6-Jan-13 10:17

6-Jan-13 10:17

That was still left from the previous version. I corrected the original answer.

The rows aren't deleted until you call AcceptChanges. They are only marked to be deleted. So depending if you have a database where you want to reflect the changes, you can first mark the rows to be deleted, actually delete from a database and the accept any pending changes.

Have a look at DataTable.AcceptChanges Method[^]

The need to optimize rises from a bad design.My articles[^]

Member 97041536-Jan-13 10:26

6-Jan-13 10:26

Accept changes was called. As per the edit in my previous post, only some of the rows with zeros have been removed?
Is the indexing here working correctly? I've seen other methods were the loop starts at the bottom of the table.

Wendelius6-Jan-13 11:20

6-Jan-13 11:20

You're correct, looping from the end is working since when an item is removed, it would be 'skipped' if looping forward.

The need to optimize rises from a bad design.My articles[^]

Member 97041536-Jan-13 11:45

6-Jan-13 11:45

Sorry - I didn't notice your loop was starting at the bottom D'Oh! | :doh:

I will try and figure out why only some zeros are being removed. Thanks for your help.

Wendelius6-Jan-13 12:06