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Alex Dunlop9-Jun-21 19:16

9-Jun-21 19:16

Hi,
I tried this code:

<pre lang="C#"> if (DGVName.Rows.Count >= 1)
            {
                foreach (DataGridViewRow row in DGVName.Rows)
                {
                    row.HeaderCell.Value = (row.Index + 1).ToString();
                }
            }

But it gives the following runtime error: WTF | :WTF:

System.ArgumentOutOfRangeException: 'Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index'

Re: How to add row headers to DataGridView?

OriginalGriff9-Jun-21 20:13

OriginalGriff

9-Jun-21 20:13

None of the code you show uses an index: those are referenced via square brackets.
So that is the wrong code, and you need to use the debugger to find out exactly where in your code the exception is happening.

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Re: How to add row headers to DataGridView?

Alex Dunlop9-Jun-21 21:53

Alex Dunlop

9-Jun-21 21:53

I tried this code which is the same as DataGridViewRow.HeaderCell Property (System.Windows.Forms) | Microsoft Docs[^]Microsoft Reference

int rownum = 1;
            foreach (DataGridViewRow row in DGVName.Rows)
            {
                if (row.IsNewRow) continue;
                {
                    row.HeaderCell.Value = "Row " + rownum;
                    rownum = rownum + 1;
                }
            }

The same error occurs. Please help me.

modified 10-Jun-21 4:03am.

Re: How to add row headers to DataGridView?

OriginalGriff9-Jun-21 22:07

OriginalGriff

9-Jun-21 22:07

And I tried your code in my DGV and it works without problem:

private void FrmMain_Shown(object sender, EventArgs epp)
    {
    string strConnect = SMDBSupport.SMInstanceStorage.GetInstanceConnectionString("Testing");
    using (SqlConnection con = new SqlConnection(strConnect))
        {
        try
            {
            con.Open();
            using (SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM myTable", con))
                {
                DataTable dt = new DataTable();
                da.Fill(dt);
                myDataGridView.DataSource = dt;
                }
            }
        catch (Exception ex)
            {
            Debug.WriteLine(ex.ToString());
            }
        }
    }

private void MyButton_Click(object sender, EventArgs e)
    {
    foreach (DataGridViewRow row in myDataGridView.Rows)
        {
        row.HeaderCell.Value = (row.Index + 1).ToString();
        }
    }

You need to use the debugger to find out exactly which line of code is throwing the exception - because I don't think it's in the code you think it is!

Re: How to add row headers to DataGridView?

Alex Dunlop9-Jun-21 22:10

Alex Dunlop

9-Jun-21 22:10

This part

row.HeaderCell.Value = (row.Index + 1).ToString();

throws an exception.
I use generalized form in my code so I can use it as a dll file in every project.

Re: How to add row headers to DataGridView?

OriginalGriff9-Jun-21 22:25

OriginalGriff

9-Jun-21 22:25

Strange.
It definitely doesn't for me, so it's got to be something to do with your data and / or the DGV itself.
I'd start by breaking it down: put each "dot point" in a separate variable and see which "bit" gives a problem:

int i = row.Index;
i++;
string s = i.Tostring();   // Can't see this failing! :laugh:
var hc = row.HeaderCell;
hc.Value = s;

I'm guessing it's something to do with the HeaderCell reference, but it's worth using the debugger to see how many times it goes round that loop before it fails as well ...

Re: How to add row headers to DataGridView?

Alex Dunlop9-Jun-21 22:39

Alex Dunlop

9-Jun-21 22:39

I checked it. The error occurs in the first loop. Of course, I'm using advanced DataGridView (because of its filter capability). Maybe, I should use native DGV instead.

Re: How to add row headers to DataGridView?

OriginalGriff9-Jun-21 22:41

OriginalGriff

9-Jun-21 22:41

That would explain the difference between your code and mine ...

You can filter standard DGVs using a binding source - didn't we tell you that a week ago or so?

Re: How to add row headers to DataGridView?

Alex Dunlop9-Jun-21 23:08

Alex Dunlop

9-Jun-21 23:08

I'm going to change them with standard DGV.

Re: How to add row headers to DataGridView?

Alex Dunlop10-Jun-21 0:02

Alex Dunlop

10-Jun-21 0:02

There was an update to advanced DataGridView. I updated it and the issue solved. The filter function also has very rapid response like Excel.

Re: How to add row headers to DataGridView?

OriginalGriff10-Jun-21 0:24

OriginalGriff

10-Jun-21 0:24

How can i read a xml file with Linq? c#

bart10008-Jun-21 9:07

bart1000

8-Jun-21 9:07

i'll try to read a cwe xml file. The problem is i have not good solution read it in a good way out

That is a xml file
CWE - Downloads[]

I'll find for example ID "1004" and will read all Items behind.
When i will read value from <background_detail> i find not a way to read this out

XElement xelement = XElement.Load(@".\cwec_v4.4.xml");

var value = from cwe in xelement.Elements().Elements()
                where (string)cwe.Attribute("ID") == "1004"
                select cwe;

foreach (XElement xEle in value)
{
    Console.WriteLine(xEle.Value);
}

var result = xelement.Elements().Elements()
             .Where(x => x.Attribute("ID").Value == "1004")
             .Elements().Where(x => x.Name == "Background_Details")
             .Elements().Where(x => x.Name == "Background_Detail")
             .Select(x => x.Value);

Have somebody experience and can help me

modified 8-Jun-21 16:20pm.

Re: How can i read a xml file with Linq? c#

Gerry Schmitz8-Jun-21 19:43

Gerry Schmitz

8-Jun-21 19:43

Create a class from the xml, and use that to access the xml.

.net - Generate C# class from XML - Stack Overflow

How to deserialize an object using XmlSerializer | Microsoft Docs

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

Re: How can i read a xml file with Linq? c#

Richard Deeming8-Jun-21 21:29

Richard Deeming

8-Jun-21 21:29

The XML document has a default namespace. You need to use that to select elements by name:

var document = XDocument.Load(@".\cwec_v4.4.xml");
var ns = document.Root.Name.Namespace;
int idToFind = 1004;

string detail = doc.Descendants(ns + "Weakness")
    .Where(el => (int)el.Attribute("ID") == idToFind)
    .Elements(ns + "Background_Details")
    .Elements(ns + "Background_Detail")
    .Select(el => el.Value)
    .FirstOrDefault();

If you want to read multiple values from a single weakness, you'll want to cache the Weakness element:

XElement weakness = document.Descendants(ns + "Weakness")
    .FirstOrDefault(el => (int)el.Attribute("ID") == idToFind);

if (weakness != null)
{
    string description = (string)weakness.Elements(ns + "Description");
    string detail = (string)weakness.Element(ns + "Background_Details").Element(ns + "Background_Detail");
    ...
}

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

Re: How can i read a xml file with Linq? c#

bart10009-Jun-21 4:12

bart1000

9-Jun-21 4:12

Thanks a lot, it works wonderfully Smile | :)

Is there any SQL Server on the cloud for free?

Alex Dunlop8-Jun-21 8:15

Alex Dunlop

8-Jun-21 8:15

Hi,
I want to make a managerial app using Xamarin. Is there any free SQL Server on the cloud which I can use in Visual Studio during app development (and as a database source for my app)?
I just only need to have a small amount of storage. My clients will be less than 100.

Re: Is there any SQL Server on the cloud for free?

OriginalGriff8-Jun-21 10:45

OriginalGriff

8-Jun-21 10:45

There are some - normally associated with free websites - but ... would I use one? Not on your Nellie!

They are free for a reason: very limited storage, very poor or non-existent / expensive tech support, availability and speed can be very low. You really do get what you pay for!
"100 clients" doesn't necessarily mean "low storage volume", it depends on the number of clients and the space each will use. Add to that, that space is not the same as bandwidth / processing time: responses need to be timely as well as small!

And these apply to the website and the DB - so unless you really don't care for security, uptime, or space, I'd pay for it. There are good one available cheap, but use Google to find one i your country if possible - it makes support much easier and (hopefully) quicker.

Re: Is there any SQL Server on the cloud for free?

Alex Dunlop9-Jun-21 4:16

Alex Dunlop

9-Jun-21 4:16

Azure SQL Service has a trial period for use. Is it possible to put an SQLite database file in the cloud and use the cloud IP address for reading/writing database on clients' devices?

Re: Is there any SQL Server on the cloud for free?

OriginalGriff9-Jun-21 4:26

OriginalGriff

9-Jun-21 4:26

That is a spectacularly bad idea, and most installations of SQL Server will not allow it - to do that you have to expose the whole DB server to the internet along with all the DBs it handles, with all the security problems that opens up!

How to dynamically escape a character?

Joseline Riker7-Jun-21 13:25

Joseline Riker

7-Jun-21 13:25

I recently ran into a problem where I'm running a C# program on the Windows command line and the % character is breaking things. So it's like runthisprogram.exe -variables -outputname "I am a filename 100%.mkv".

The % in the above path when passed to the application errors. They say I have to escape the % to get it to work and they are correct, but if

I am a filename 100%.mkv

is in a variable, how do I dynamically search the contents and if there is a % replace it with %%

Thanks.

Re: How to dynamically escape a character?

Dave Kreskowiak7-Jun-21 15:06

Dave Kreskowiak

7-Jun-21 15:06

How about

myString = myString.Replace("%", "%%");

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Dave Kreskowiak

Re: How to dynamically escape a character?

OriginalGriff7-Jun-21 19:50

OriginalGriff

7-Jun-21 19:50

To add to what Dave has said, that sounds like they are giving you the runaround: unless you are creating a batch or powershell file from your string then the '%' character has no special significance in either a command line to an application, or a filename. You can happily execute a C# program and hand it a single '%' as part of a file name:

using System;

namespace OneOffConsole
    {
    class Program
        {
        static void Main(string[] args)
            {
            foreach (string s in args)
                {
                Console.WriteLine(s);
                }
            }
        }
    }

Microsoft Windows [Version 10.0.19043.985]
(c) Microsoft Corporation. All rights reserved.

C:\Users\PaulG>cd "D:\Documents\AA Backed Up\My Projects\OneOffJobs\OneOffConsole\bin\Debug"

C:\Users\PaulG>D:

D:\Documents\AA Backed Up\My Projects\OneOffJobs\OneOffConsole\bin\Debug>oneoffconsole -variables -outputname "I am a filename 100%.mkv"
-variables
-outputname
I am a filename 100%.mkv

D:\Documents\AA Backed Up\My Projects\OneOffJobs\OneOffConsole\bin\Debug>dir >"x 100%.txt"

D:\Documents\AA Backed Up\My Projects\OneOffJobs\OneOffConsole\bin\Debug>type "x 100%.txt"
 Volume in drive D is GriffData
 Volume Serial Number is 4CA5-2F85

 Directory of D:\Documents\AA Backed Up\My Projects\OneOffJobs\OneOffConsole\bin\Debug

08/06/2021  06:39    <DIR>          .
08/06/2021  06:39    <DIR>          ..
20/06/2019  17:39         4,079,616 itextsharp.dll
20/06/2019  17:39         3,180,097 itextsharp.xml
20/06/2019  17:39           169,984 itextsharp.xmlworker.dll
08/06/2021  06:35             4,608 OneOffConsole.exe
25/06/2019  06:47               189 OneOffConsole.exe.config
08/06/2021  06:35            19,968 OneOffConsole.pdb
08/06/2021  06:39                 0 x 100%.txt
               7 File(s)      7,454,462 bytes
               2 Dir(s)  805,619,617,792 bytes free

D:\Documents\AA Backed Up\My Projects\OneOffJobs\OneOffConsole\bin\Debug>

But that's worrying to me: because '%' isn't a special character in Windows, or C# - but it is in SQL, and only when passing strings to a database without using parameterised queries.
And that's very dangerous as it leaves an application wide open to something called "Sql Injection" which can destroy your entire database. Applications should always use Parameterized queries instead.

When you pass strings directly, you cause problems because SQL receives commands like:

SQL

SELECT * FROM MyTable WHERE StreetAddress = 'Baker's Wood'

The quote the user added terminates the string as far as SQL is concerned and you get problems. But it could be worse. If I come along and type this instead: "x';DROP TABLE MyTable;--" Then SQL receives a very different command:

SQL

SELECT * FROM MyTable WHERE StreetAddress = 'x';DROP TABLE MyTable;--'

Which SQL sees as three separate commands:

SQL

SELECT * FROM MyTable WHERE StreetAddress = 'x';

A perfectly valid SELECT

SQL

DROP TABLE MyTable;

A perfectly valid "delete the table" command

SQL

--'

And everything else is a comment.
So it does: selects any matching rows, deletes the table from the DB, and ignores anything else.

I'd suggest that you ask the developers why the '%' character is causing problems within a well-formed and quoted filename, and ask to see the code that it affects.

Re: How to dynamically escape a character?

Richard MacCutchan7-Jun-21 21:14

Richard MacCutchan

7-Jun-21 21:14

Joseline Riker wrote:
The % in the above path when passed to the application errors.

But you have not explained what error or where it occurs. As it stands using the % character in a filename is perfectly legal.

Re: How to dynamically escape a character?

Eddy Vluggen9-Jun-21 9:49

Eddy Vluggen

9-Jun-21 9:49

Try

I am a filename/Am I? .sav

File names are that; they should adhere to the naming rules, and aren't intended as a label.

Bastard Programmer from Hell Suspicious | :suss:

"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

INotifyPropertyChanged/Changing: more useful in WPF compared to WinForms ?

BillWoodruff7-Jun-21 11:35

BillWoodruff

7-Jun-21 11:35

note: this is not about AOP, IL weaving, Furty, PostSharp, etc., although those facilities are related to this discussion.

Context: in WinForms both these notification methods have, imho, very limited uses.

Do you use these mechanisms more frequently in WPF ? Are they valuable to you ? Essential/integral in MVVM ?

Have you ever developed your own notification-with-cancellation mechanism (i have, for WinForms).

0) there's an excellent overview of how INotifyPropertyChanged can be used in different C# versions by SO's resident genius, Marc Gravell: [^]

1) INotifyPropertyChanging has no cancel mechanism ... unless you consider throwing an error in some context you have no control over sweet-smelling code OMG | :OMG:

According to PostSharp docs: "INotifyPropertyChanging interface is not portable (in Xamarin, it is even a part of a different namespace)."

2) INotifyPropertyChanged is just post-facto notification. There does appear to be a special benefit in using it with SQL and Linq: [^] ... i've never played with that.

Of course, you could trigger update of a binding connection. And, using Caller Information Attributes is easy in a Notify* changed handler ... imho, those attributes are of very limited value.

3) through "heroic" programming, you can create custom EventArgs that inherit from the INotify* versions and extend them to implement cancellation. however, in your subscribing objects' handlers you will have to cast the incoming args to their extended form.

there's an outstanding 2 article series here on CP from 2007: [^] that shows this kind of EventArgs extending as a way to get cancellation.

«One day it will have to be officially admitted that what we have christened reality is an even greater illusion than the world of dreams.» Salvador Dali

modified 7-Jun-21 22:00pm.

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