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Yes, ASP.NET Identity requires distinct SignInManager<TUser> and UserManager<TUser> classes.
The management of user accounts, including their creation, updating, and deletion, password resets, and email address confirmations, is under the purview of the UserManager<TUser> class
SignInManager<TUser> class is responsible for handling the authentication and sign-in process for the application
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This is my first time that i post here and i hope that topic is correct is placed.
Please who can help me?
Error message is:
An unhandled exception of type 'System.InvalidCastException' occurred in System.Data.dll
Additional information:
This rows give error (the code was writed for MySQL and i have self changed to MS Access):
Dim len As Long = rd.GetBytes(0, 0, Nothing, 0, 0)
Dim array(CInt(len)) As Byte
rd.GetBytes(0, 0, array, 0, CInt(len))
pic = New PictureBox
Dim ms As New System.IO.MemoryStream(array)
Dim bitmap As New System.Drawing.Bitmap(ms)
pic.BackgroundImage = bitmap
Full Code:
Imports System.Data.OleDb
Public Class Form1
Dim con As OleDbConnection
Dim cmd As OleDbCommand
Dim rd As OleDbDataReader
Private WithEvents pic As New PictureBox
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'Dim con As OleDbConnection
'Dim cmd As OleDbCommand
'Dim rd As OleDbDataReader
con = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\database.accdb;")
con.Open()
cmd = New OleDbCommand("select * from MyTable", con)
rd = cmd.ExecuteReader
MsgBox("connected")
con.Close()
MsgBox("disconnected")
End Sub
Sub LoadData()
con = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\database.accdb;")
con.Open()
cmd = New OleDbCommand("select * from MyTable", con)
rd = cmd.ExecuteReader
While rd.Read
Dim len As Long = rd.GetBytes(0, 0, Nothing, 0, 0)
Dim array(CInt(len)) As Byte
rd.GetBytes(0, 0, array, 0, CInt(len))
pic = New PictureBox
Dim ms As New System.IO.MemoryStream(array)
Dim bitmap As New System.Drawing.Bitmap(ms)
pic.BackgroundImage = bitmap
FlowLayoutPanel1.Controls.Add(pic)
End While
rd.Close()
con.Close()
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
LoadData()
End Sub
End Class
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sdfsdfsdfewrew3feff wrote: This is my first time that i post here
And yet you've apparently been a member for 12½ years, and posted 22 messages. Did you mean this is your first post in the ".NET Core" forum? Or have you managed to grab someone else's account by mistake?
sdfsdfsdfewrew3feff wrote: select * from MyTable
If you're only reading one column, then only select that one column. If you use select * from ... then you're subject to the whims of the database engine as to which order the columns are returned in.
You're presumably getting the InvalidCastException on the rd.GetBytes line, which suggests the first column being returned by your query is not your image column.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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Sorry, Richard. I was forget and it long time ago.
When i select a column than i get new error "From".
Additional information: The FROM clause contains a syntax error.
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The only queries you've shown are select * from MyTable, which wouldn't produce that error.
Perhaps your real table name is a reserved word?
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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sdfsdfsdfewrew3feff wrote: This is my first time that i post here
No it's not! I remember you from a couple of exchanges about 8 years ago.
You're FINALLY providing proper detail to actually help you this time! 
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Hi Dave Kreskowiak, i was forget and you me not.
Long time ago i have download opensource projects.
Welcome back Dave and how are you?
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sdfsdfsdfewrew3feff wrote: "select * from MyTable"
Using the asterisk means the database is free to return the columns (all columns) in any order that it wants.
So if your table as more than one column then you have no idea at all what the first column actually is.
Thus if you assume that the first column is of a certain type like a varchar but you use it like an int, and code it that way, then you will get errors. Very like a cast error.
Your SQL should look like the following.
select col1, col2, col3 from MyTable
If you only want one column then of course only specify those.
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----The Sample XML File
<AuditResult name="Server Baseline" created="2/14/2023 3:16:19 AM" type="Assessment run by Administrator">
<Section name="Operating System" state="Compliant" further-state="">
<Result name="Computer Name" type="report">DEVSTUDIO </Result>
<Result name="Operating System" type="report">Microsoft Windows Server 2008 R2 Standard </Result>
</Section>
<Section name="Operating System (Windows Server 2008 R2)" state="Not Compliant" further-state="">
<Result name="System Partition" type="compliance" state="Compliant" further-state=""> </Result>
<Result name="Role & Feature - .NET Framework" type="compliance" state="Compliant" further-state=""> </Result>
<Result name="Windows Firewall - Private Profile Off" type="compliance" state="Compliant" further-state=""> </Result>
<Result name="Windows Firewall - Domain Profile Off" type="compliance" state="Compliant" further-state=""> </Result>
</Section><code></code>
</AuditResult>
------------------
The above is my xml file, i am using dataset to populate in the gridview i am able to get the child node information but along with parent i am unable to do it. PFB the code
Dim Opf As New OpenFileDialog()
Opf.Filter = "XML File | *.xml"
Opf.FileName = ""
If Opf.ShowDialog() = DialogResult.OK Then
Dim fcontent As String
Dim fpath As String
fpath = Opf.FileName
Using sr As StreamReader = New StreamReader(fpath)
DataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells
DataGridView1.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells
DataGridView1.DefaultCellStyle.WrapMode = DataGridViewTriState.True
fcontent = sr.ReadToEnd
'MsgBox(fcontent)
Dim sfcontent As StringReader
sfcontent = New StringReader(fcontent)
Dim doc As XmlDocument = New XmlDocument()
doc.Load(sfcontent)
Dim naudit As XmlNode = doc.SelectSingleNode("/AuditResult/@name")
Dim naudita = naudit.InnerText
nlblaudit.Text = naudita
Dim nauditc As XmlNode = doc.SelectSingleNode("/AuditResult/@created")
Dim naudit1 = nauditc.InnerText
Dim nauditb As XmlNode = doc.SelectSingleNode("/AuditResult/@type")
Dim naudit2 = nauditb.InnerText
nlblauditcreated.Text = naudit2 & " - Created" & " : " & naudit1
Dim ds As New DataSet()
ds.ReadXml(New StringReader(fcontent))
DataGridView1.DataSource = ds.Tables(2)
For i As Integer = 0 To Me.DataGridView1.Rows.Count - 1
If Not IsDBNull(Me.DataGridView1.Rows(i).Cells(2).Value) Then
If Me.DataGridView1.Rows(i).Cells(2).Value = "Compliant" Then
Me.DataGridView1.Rows(i).DefaultCellStyle.BackColor = Color.LightGreen
ElseIf Me.DataGridView1.Rows(i).Cells(2).Value = "Not Compliant" Then
Me.DataGridView1.Rows(i).DefaultCellStyle.BackColor = Color.LightPink
End If
End If
Next
End Using
End If
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I have recently starting getting a memory resources error with System.Design. The application has been running fine for years and this just started popping up without any code changes. This has been encountered on multiple PCs.
Could not load file or assembly 'System.Design, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. Not enough memory resources are available to process this command. (Exception from HRESULT: 0x80070008)
The application is running on .NET 4.6.1. The app is taking up around 400 MB of memory and I have over 10 GB RAM free on my PC. So I don't think it is a PC resource issue.
After the error occurs I start seeing issues in the OpenFileDialog. The icons are black squares and parts of the UI of the form don't show up. The file name and file type drop down will be missing.
Here is the stack trace:
at System.ModuleHandle.ResolveType(RuntimeModule module, Int32 typeToken, IntPtr* typeInstArgs, Int32 typeInstCount, IntPtr* methodInstArgs, Int32 methodInstCount, ObjectHandleOnStack type)
at System.ModuleHandle.ResolveTypeHandleInternal(RuntimeModule module, Int32 typeToken, RuntimeTypeHandle[] typeInstantiationContext, RuntimeTypeHandle[] methodInstantiationContext)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.PopulateNestedClasses(Filter filter)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.GetListByName(Char* pName, Int32 cNameLen, Byte* pUtf8Name, Int32 cUtf8Name, MemberListType listType, CacheType cacheType)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.Populate(String name, MemberListType listType, CacheType cacheType)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.GetMemberList(MemberListType listType, String name, CacheType cacheType)
at System.RuntimeType.GetNestedTypeCandidates(String fullname, BindingFlags bindingAttr, Boolean allowPrefixLookup)
at System.RuntimeType.GetMember(String name, MemberTypes type, BindingFlags bindingAttr)
at System.Type.GetMember(String name, BindingFlags bindingAttr)
at Microsoft.VisualBasic.CompilerServices.Symbols.Container.LookupNamedMembers(String MemberName)
at Microsoft.VisualBasic.CompilerServices.Symbols.Container.GetMembers(String& MemberName, Boolean ReportErrors)
at Microsoft.VisualBasic.CompilerServices.NewLateBinding.LateSet(Object Instance, Type Type, String MemberName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, Boolean OptimisticSet, Boolean RValueBase, CallType CallType)
at Microsoft.VisualBasic.CompilerServices.NewLateBinding.LateSet(Object Instance, Type Type, String MemberName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments)
at FormLookAndFeel.ApplyTheme(Object& source, List`1& lstIgnoreTheme, ToolStripType& toolStripType) in C:\Users\JoshWilliams_k0t30jx\Documents\PROJECTS\Sherpa\COM_v1\Theming\FormLookAndFeel.vb:line 47
at FormLookAndFeel.BlueTheming(Object& form, List`1& lstButton, List`1& lstHeading, List`1& lstIgnoreTheme, ToolStripType& toolStripType) in C:\Users\JoshWilliams_k0t30jx\Documents\PROJECTS\Sherpa\COM_v1\Theming\FormLookAndFeel.vb:line 17
at frmAdmin.frmAdmin_Load(Object sender, EventArgs e) in C:\Users\JoshWilliams_k0t30jx\Documents\PROJECTS\Sherpa\COM_v1\frmAdmin.vb:line 1225
The code that encounters the error loops through all controls on the form and sets the font size, fore color and back color based on control type. As I said above this has worked for years without an issues. This just started to appear.
Any assistance would be appreciated. Thank you!
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It may not be a memory issue, but it certainly could be a handle leak issue. It sounds like you're running the handle pool dry because you're not freeing resources properly, like Bitmaps, Pens, or other drawing objects.
Open Task Manager, Details tab, right-click the column header row and pick "Select columns". Turn on Handles and GDI Objects. Then go look at you app in the list. If the handles count just keeps climbing over time, you're not releasing objects properly.
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You may be right, but how common is it is to address "bitmaps, pens or other drawing objects" directly when you are running dotNet? Usually, that means C# or -as it looks like here - VB, with its GC. Usually it also means UI tools at a higher level, such as WPF.
It is still possible you have (functionally obsolete, but still valid) pointers to a large number of objects so that they can't be GCed, and these objects hold handles so that they can't be GCed. It could still be a handle leak issue, but the fundamental problem may lie in (say) C# objects not being made GCable - which is generally done by removing the last reference (i.e. pointer) to them, not by any explicit freeing operation.
In C#, you can use 'using' to hint the GC that it may free an object, but this is just a hint to reduce memory load. The GC should be running a GC cycle when memory gets low without such hints. I never worked in VB, and don't know if it has anything similar to 'using'.
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It's actual quite easy. For example, if you create a Bitmap object, you're just creating a wrapper around an unmanaged GDI object with a handle associated with it. Failing to Dispose the Bitmap properly and letting the Bitmap go out of scope will allow the GC to collect the wrapper object, and call the Dispose method on it, but not in a deterministic manner, meaning you have no idea when the handle will be released. This can result in you piling up handles waiting to be released and exhausting the handle pool before the GC can get around to freeing the Bitmap objects.
The same goes for all GDI related objects, files, and anything else being backed by unmanaged Windows resources.
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Possible? Sure. Common? ???
Ordinarily, dotNet objects are managed. Is is possible, through System.Runtime.InteropServices to call unmanaged code, and obtain pointers to unmanaged data objects. I don't think very many dotNet programmers will do that in cases where there is a managed alternative.
Re. Dispose: Sure, you do not know exactly when GC will come in and release the memory / handles occupied. But if resources run low, the GC will attempt to release non-referable resources; it will not just sit down and wait for the system to crash, the way you seem to suggest.
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trønderen wrote: Ordinarily, dotNet objects are managed
Yup. The reference is, but things like handles aren't. A lot of the runtime is a wrapper around the existing libraries.
Means one cannot rely on the GC to close those neatly if there's no dispose called.
Bastard Programmer from Hell 
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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A trick that I use is to wrap the objects I use into common classes so that I use them and free them up as soon as possible. The classes all have a Draw method and, in the Draw, I acquire the resource, paint it to the screen, and then release the resource immediately. The code I use to draw the objects doesn't need a Dispose method because the underlying object is disposed as soon as it is finished with.
I find that this really helps me keep track of my allocations.
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trønderen wrote: Possible? Sure. Common? ???
You'd be amazed at how many people don't know this stuff.
trønderen wrote: Re. Dispose: Sure, you do not know exactly when GC will come in and release the memory / handles occupied. But if resources run low, the GC will attempt to release non-referable resources;
If memory runs low, the GC will jump in and execute a collect. The GC doesn't look at the handle pool at all to determine if it should run or not. If your code is leaking handles like crazy, but memory is not being stressed at all, the GC will not collect.
Yes, I've seen it happen myself, with a service that Dell wrote, back in the day.
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Dave Kreskowiak wrote: freeing resources properly, like Bitmaps, Pens, or other drawing objects.
The originating error is "Could not load file or assembly"
How would graphic resources cause that?
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Keep reading the error message:
Not enough memory resources are available to process this command
That can be memory limited, handle limited, or other resources or issues, like memory fragmentation.
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Dave Kreskowiak wrote: That can be memory limited, handle limited, or other resources or issues, like memory fragmentation.
However I was asking about the following specifically which is why I referenced it:
"Bitmaps, Pens, or other drawing objects."
So you are suggesting that they could have loaded so many graphic objects that it is those that caused the memory to fill up and that it did so without running into a graphic resource error which I believe is a different error?
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Yes! Creating such objects and not properly freeing them CAN and DOES trigger out of memory exceptions, not resource exceptions.
I don't have to time to write up a test app right now, but there's nothing stopping you from trying it.
Oh, and exhausting the Windows handle table can crash various things in Windows, like an OpenFileDialog or MessageBox, and even crash Windows itself.
Every object type in Windows has a handle assigned to it. A handle is just a void pointer to a data structure in memory. Windows, buttons, menus, icons, bitmaps, pens, mutexes, threads, a structure, opening a file, basically, anything in Win32 that has a pointer or handle type that begins with "h", all of these objects end up in the handle (or object) table in Windows. Pretty much ... EVER-Y-THANG.
Read up on the Object Manager here[^].
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Can dotNet run out of memory if the computer has plenty?
If you run e.g. Task Manager | Performance | Memory, or Resource Monitor | Memory (I guess there are similar tools from 3rd parties as well), and they tell you that you've got lots of free memory, could dotNet still report that you are out of memory? Can it decide not to use what is available?
If any free (that includes 'Standby' in Resource Monitor terms) memory can be used by dotNet, keeping a window open with Resource Monitor or Task manager would be a very simple way to see if your problem is with memory or with, say, handles.
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trønderen wrote: Can dotNet run out of memory if the computer has plenty?
Yes, for a variety of reasons. For example, large heap fragmentation. You try to allocate a large object, but there is not a "hole" in the Large Object heap big enough to allocate the object, even though there is technically enough memory to hold it if you add up all the "holes" to get the size of "available" memory.
Quote: If any free (that includes 'Standby' in Resource Monitor terms) memory can be used by dotNet, keeping a window open with Resource Monitor or Task manager would be a very simple way to see if your problem is with memory or with, say, handles.
If you're running into a handle exhaustion problem, if you try to even launch Task Manager, you can end up with it crashing just trying to create its own window.
You are thinking in simple terms of everything. "Free memory" is treated as a single contiguous block in Task Manager, but that's not how memory is really represented. What you're not seeing is "largest available block" of memory.
You also seem to think Windows can track an unlimited number of objects in the Object Manager handle table. It can't. Read up on it here[^].
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You should be able to track it down with GFlags
Don't let the documentation scare you, it's not only for device driver developers.
How to use Gflags
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JoshWilliams wrote: The application has been running fine for years...taking up around 400 MB of memory and I have over 10 GB RAM...VisualBasic
First noting of course that a 32 bit application is not going to use 10 GB of memory even if it exists. Last time I looked into this (last year) the apps that had been built years ago required setting a flag explicitly to make them into 64 bit apps. There it a attribute somewhere that you can read (and log) to see exactly whether it is 32/64 bit. I suggest using that explicitly to check.
Second what is missing in your description is whether you have also been modifying that same application for years. If you haven't then the problem is with the environment or due to load. If you have been modifying then the problem could either be due to the modifications or to load.
You can test for load problems at least for memory by starting the application up with a reduced memory space. That artificially forces memory problems to show up. Of course you must still exercise the application after that.
JoshWilliams wrote: Here is the stack trace:
The stack trace for a resource exhaustion is generally almost worthless because the exhaustion is just telling you where it ran out.
It does NOT tell you, most of the time, where the code exists that is using it all up.
The entire application is responsible for the resources. So code completely un-associated with the code that you are looking at could be doing something that uses it up.
I will mention the following because the error occurs when loading an assembly. This unfortunately is very esoteric and not easy to follow (even when someone already knows something about memory handling.) But it is something that developers should be aware of.
Large object heap (LOH) on Windows | Microsoft Learn[^]
I think there might be a way to increase this. If you do change it and the error goes away you must keep in mind that you have put a bandaid on a gushing wound and you still need to find the actual problem.
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