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Set a permanent value of a variable without using a database

I don't know how to describe it thoroughly in the title, but I need to set a permanent value of a variable/flag once a process has return true and maybe set some flag in the program itself the value rather than saving it to database. And once that variable/flag has already have that value then the program won't run the process again and just use the value. Is it possible? I'm using VB.Net. I can't use the database because database can be overridden and change values by using query. Thanks in advance!

You can simply use binary/XML serialization in a file to save the state of that variable through your program. Every time you restart your app you can access the value from that file to get its current state.
You can look at this example - http://www.centerspace.net/examples/nmath/csharp/core/binary-serialization-example.php
Basically, you will not save the value in the database but in a file. Anyways you need to persist the value somewhere.

Some ways below
You did not specify if you are afraid that your application or another one could change the value
How I would do it
My ideas below
1)You could use an xml file for example and zip a copy of it with a strong password. Every time you update the first xml you will update also the encrypted zipped xml.You can use a FileSystemWatcher and capture any file change, so if something/someone has changed the file you just get a new copy from the zip
2)You can store the value in the DB and add a trigger to prevent delete/update
for example
-- delete trigger
CREATE TRIGGER Function_Value_Deleted
ON [dbo].[FunctionsValueTb]
AFTER DELETE
AS
BEGIN
SET NOCOUNT ON;
IF EXISTS (
SELECT [Flag] FROM deleted
)
BEGIN
ROLLBACK;
RAISERROR ('Record deletion is not allowed...', 16, 1);
END
END
*You can use also use THROW rather than RAISERROR
**Do the same for the insert and update actions
***You can also store the value into a log table or send an email

I found myself in a situation quite similar to yours a couple of days ago.
In the end, I decided to use the settings functionaly provided by .NET: it is easy to use and maintain, and so far it has given me good results.
Yo can see here what I am talking about:
Best practice to save application settings in a Windows Forms Application
That thread refers to C# but is easily applicable for VB.NET: I just had to follow the same steps in order to add the Settings file:
Right click on the project in Solution Explorer, choose Properties.
Select the Settings tab, click on the hyperlink if settings doesn't
exist. Use the Settings tab to create application settings. Visual
Studio creates the files Settings.settings and
Settings.Designer.settings that contain the singleton class Settings
inherited from ApplicationSettingsBase
And then, from my code, I use the settings like this:
Dim lastExecDate As Date = My.Settings.LastSuccessfulExecution
lastExecDate = lastExecDate.AddDays(1)
// Perform my next execution and do other stuff
My.Settings.LastSuccessfulExecution = lastExecDate
My.Settings.Save()
Next time you retrieve the parameter LastSuccessfulExecution, it will have the updated value.
One more remark, as stated in the post that I linked above:
Note that you need to set the scope property of your settings. If you
select Application scope then Settings.Default.< your property > will
be read-only
Finally, I see that you are using this to store the expiration date of a product, so you don't want the user messing around with it. According to this post, the actual values of the parameters are stored in an Application Data user folder. It is somehow obfuscated since it is not that easy to find and besides it contains a hash on its name... I don't know if that is well hidden enough for you.

If you want the value only to exist in memory when the application is running then you can use the main thread of the application and use:
int slotData = randomGenerator.Next(1, 200);
//to set the data
Thread.SetData(Thread.GetNamedDataSlot("SomeDataKey"), slotData);
//to get the data
int newSlotData = (int)Thread.GetData(Thread.GetNamedDataSlot("SomeDataKey"));
Or you can use the Windows Registry if your app only runs on Windows, if not then you would have to write the value/object to a file and read it from there.

Saving Data On C# Wpf

How can I save my added buttons when closing the program ? Each time I hit an add button I'm creating a new title which type is button.And each title have it's own specific words.So I must save the words in buttons at the same time.

Find out what data needs to be stored. > Define a Model
Define how the Data will be stored > e.g. XML-Serialisation, JSON or whatever
Define where Data will be stored, e.g. Database, File
Define when the Configuration is read and saved
eg: read on startup, save on shutdown
Handle your Configuration Data to generate your buttons
Its all up to you. :)
An easy solution might be using XmlSerializer, which is documented here.

C# translate database data using resx file

In my project (I am using azure storage) I have some data that I want to translate. I have the resource system in place for translations. I have a table in cloud which has name property. I want to translate it somehow.
One option is to create all the entries in database for each language which I don't prefer as it would create a lot entries along with the name.
Is there a smart way to use the resx mechanism I have in place?
So the table has multiple properties and one is name. Name could be anything like Mud, rock etc. Now I want to translate Mud into different language. Something like Texts.Mud would return me the correct value.
But lets say I get data like this
var data = some query;
string translatedName = Texts.data[0].name; // this won't work

You should instead add more columns in the database, each for a different language and select the column based on the user language.
Other solution is to have a transaltion mechanism (a custom class for example), where you pass the original database result (say data[0].name) to a query and it returns the translated value for you.

How do I determine if a record already exists in a DataTable?

I have a DataTable that I am binding it to a GridView on my ASP.NET page. I also allow editing and insertion.
Upon saving/insertion, I need to determine if there is a duplicate description in the Gridview.
How can I accomplish this?

Any way the data which you are binding will have the unique id.
So after binding check for that id whether it is there or not in datatable.We can't say more than this unless you explain it more.

We may need some more information on what kind of database you are using to give you the right answer, but I'll take a swing anyway.
First, you need to have a PRIMARY KEY on your database table for several reasons including a default index and insuring uniqueness. Second, you can configure the table to have a UNIQUE INDEX on the description column. This will prevent the insertion of duplicate data at the database level. But, once you do that you will likely get some kind of exception or error in your client application that you will need to catch and handle.
Also, you could create an AJAX function to filter the data as the user types in the new row and show them records that are similar. I did this on an app where the users would put in the same request but use slightly different wording.

Best Practice - Handling multiple fields, user roles, and one stored procedure

I have multiple fields both asp:DropDownList's and asp:TextBox's. I also have a number of user roles that change the Visible property of certain controls so the user cannot edit them. All of this data is saved with a stored procedure call on PostBack. The problem is when I send in the parameters and the control was not on the page obviously there wasn't a value for it, so in the stored procedure I have the parameters initialized to null. However, then the previous value that was in the database that I didn't want changed is overwritten with null.
This seems to be a pretty common problem, but I didn't have a good way of explaining it. So my question is, how should I go about keeping some fields from being on the page but also keeping the values in the database all with one stored procedure?

Apply the same logic when chosing what data to update as the logic you're actually using when chosing what data (and its associated UI) to render.

I think the problem is you want to do the update of all fields in a single SQL update, regardless of their value.
I think you should do some sanity check of your input before your update, even if that implies doing individual updates for certain parameters.

Without an example, it is a little difficult to know your exact circumstances, but here is a fictitious statement that will hopefully give you some ideas. It is using t-sql (MS SQL Server) since you did not mention a specific version of SQL:
UPDATE SomeImaginaryTable
SET FakeMoneyColumn = COALESCE(#FakeMoneyValue, FakeMoneyColumn)
WHERE FakeRowID = #FakeRowID
This basically updates a column to the parameter value, unless the parameter is null, in which case it uses the columns existing value.

Generally to overcome this in my update function
I would load the current values for the user
Replacing any loaded values with the newly changed values from the form
Update in db.
This way I have all the current plus everything that has been changed will get changed.
This logic will also work for an add form because all the fields would be null then get replaced with a new value before being sent to the db. You would of course just have to check whether to do an insert or update.