VB.NET

How to send a sale to PayPal in ASP.NET (and not have the ‘form’ issue)

steve@4penny.net — Thu, 26 May 2011 17:44:10 GMT

When you create a web site in ASP.NET the form tag is included for you. This issue is magnified if you use master pages (who doesn’t?).

The issue is that the code that you get from PayPal has a

tag in it, and you can’t nest form tags. So your code doesn’t post correctly when the user clicks ‘Buy Now’.

Here’s a real easy way around that. There are two ways you can do this, as a link from the code, or as a Response.Redirect from the code behind. The link will be less work, but also less flexible.

From the HTML, code something like this:

 <a href="https://www.paypal.com/cgi-bin/webscr
  ?cmd=_xclick&business=YOUR-PAYPAL-EMAIL-HERE
  &item_name=Widget
  &amount=29.00
  &undefined_quantity=1
  ¤cy_code=USD">
<img src="http://www.paypal.com/en_US/i/btn/x-click-but23.gif"
  border="0" alt="Buy Now Using PayPal" />
a>
 

If you’ll compare the above to the code that you got from PayPal, you’ll see that we converted the tags to be parameters in the query string.

From the code behind it looks like this:

 Protected Sub btnSubscribeYear_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSubscribeYear.Click
    Dim dblAmount As Double
    dblAmount = Me.txtAmount.text
 
    https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&amount=" & dblAmount & "&hosted_button_id=3IMNOTREAL3E3
End Sub
 

Here’s a list of all the arguments (not guaranteed to be complete or correct, you’ll want to check with PayPal for complete information)

Argument                Description
business                Email address associated with seller's PayPal account
quantity                Quantity of items being sold
undefined_quantity      Allows user to edit quantity
item_name               Name of item
item_number             Optional item number
amount                  Price of each item (without currency symbol)
undefined_amount        Allows user to edit the amount (good for donations)
shipping                Price of shipping
currency_code           Code for type of currency (Default appears to be USD)
first_name              Customer's first name
last_name               Customer's last name
address1                Customer's first address line
address2                Customer's second address line
city                    Customer's city
state                   Customer's state
zip                     Customer's zip code
email                   Customer's email address
night_phone_a           Customers telephone area code
night_phone_b           Customers telephone prefix
night_phone_c           Remainder of customer's telephone number

More ...

How to serialize a DataTable to a string (and back into a DataTable again)

steve@4penny.net — Tue, 24 May 2011 18:42:20 GMT

This piece of code will show how to serialize a DataTable to a string, where it can be saved to disk, and then how to read that string back into a DataTable again. Actually, we’ll have to use a DataSet to read the string (in XML format) back in, if you use a DataTable you’ll get:

DataTable does not support schema inference from Xml

Oddly, the DataSet works just fine

There are code comments for each line below, you should not have any trouble with it.

 Imports System.IO
Imports System.Xml
 
Module Module1
 
    Sub Main()
        'declare a datatable and populate it with data. Here, we call a 
        'subroutine that loads invoices from a text file.
        Dim oDT As DataTable = getAPInvoices("Data.txt")
 
        'declare a stringWriter and an XmlTextWriter
        Dim sw As New StringWriter
        Dim tw As New XmlTextWriter(sw)
        'give the table a name. This name will become the name of each row in the XML file
        oDT.TableName = "invoice"
 
        'make the XML pretty
        tw.Formatting = Formatting.Indented
 
        'write to the XmlTextWriter/StringWriter
        oDT.WriteXml(tw)
 
        'view the results
        MsgBox(sw.ToString)
 
        'declare a new DataSet. Note that we're not using a DataTable... you'll get
        'an error if you do:
        'DataTable does not support schema inference from Xml
        Dim oDSNew As New DataSet
 
        'declare a StringReader, populate it with our XML String
        Dim sr As New StringReader(sw.ToString)
 
        'read in the XML into our DataSet
        oDSNew.ReadXml(sr)
 
        'loop through it to prove it worked.
        For Each oRow As DataRow In oDSNew.Tables(0).Rows
            Console.WriteLine(oRow("vchnumwk"))
        Next
    End Sub
 

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Embed an image into an email

steve@4penny.net — Mon, 23 May 2011 17:43:08 GMT

This piece of code shows how to embed an image into an email using the System.Net.Mail namespace

 Try
    Dim strServer As String = strMailServer
 
    Dim mail As New System.Net.Mail.MailMessage(strFrom, strTo)
 
    For Each cc In strCC.Split(";")
        If cc > "" Then
            mail.CC.Add(cc)
        End If
    Next
 
    For Each bcc As String In strBCC.Split(";")
        If bcc > "" Then
            mail.Bcc.Add(bcc)
        End If
    Next
 
    Dim htmlView As Net.Mail.AlternateView = Net.Mail.AlternateView.CreateAlternateViewFromString("Here is the image... ", Nothing, "text/html")
 
    Dim oImage As New Net.Mail.LinkedResource(strFilename)
    oImage.ContentId = "myImage"
    htmlView.LinkedResources.Add(oImage)
 
    mail.Subject = strSubject
    mail.Body = strBody
    mail.Priority = intPriority
    mail.AlternateViews.Add(htmlView)
 
    Dim serv As New System.Net.Mail.SmtpClient(strServer)
 
    serv.Send(mail)
 
Catch ex As Exception
    Throw New Exception(ex.Message)
End Try
 

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URI.TryCreate examples

steve@4penny.net — Tue, 22 Mar 2011 22:55:36 GMT

Recently I needed to concatenate two strings and form a URI. I had the base stored in the site config; then we needed to add the page onto that. I wanted to be sure that I didn’t have errors if the user added or didn’t add ‘/’ to the URI in the config so I started with Path.combine. That worked (sort of) but it used the wrong ‘/’ and it generated an error.

Enter URI.TriCreate. According to the documentation this would do the trick. But the documentation didn’t have any examples; and I couldn’t figure out the syntax. How bad is the documentation if you read all the way through it and still don’t have a clue?

At any rate, I searched on line for a while and put it all together. Here are code sample for the three overloads.

A few definitions so that you don’t have the same issues that I did:

URI: Uniform Resource Identifier. A string of characters used to identify a name or a resource on the Internet.
UriKind: URIs can be Absolute or Relative. “www.devshed.us” is Absolute. “/links.aspx” is relative.

Code Snippet
 Module Module1
 
    Sub Main()
        TryCreate1()
        TryCreate2()
        TryCreate3()
    End Sub
 
    Sub TryCreate1()
        'demonstrates Uri.TriCreate(Uri,String,Uri)
        Dim UriIn As Uri = New Uri("http://devshed.us/")
        Dim strPage As String = "/links.aspx"
        Dim UriOut As Uri = Nothing
 
        If Uri.TryCreate(UriIn, strPage, UriOut) Then
            Debug.Print(UriOut.ToString)
        Else
            Throw New Exception("Invalid URI")
        End If
    End Sub
    Sub TryCreate2()
        'demonstrates Uri.TriCreate(String,Urikind, Uri)
        'this form doesn't create anything. It just tells us if the URI that we're passing 
        'in the first parameter is Relative or Absolute. Or valid at in any form
 
        'test to see if this string is a valid URI
        Dim strUrl As String = "http://devshed.us/"
 
        'placeholder for our output
        Dim UriOut As Uri = Nothing
 
        'see if our input qualifies as an Absolute URI
        If Uri.TryCreate(strUrl, UriKind.Absolute, UriOut) Then
            'yes
            Debug.Print(UriOut.ToString & " is absolute")
        Else
            'no
            Debug.Print(strUrl & " is not absolute")
        End If
 
        'see if our input qualifies as a Relative URI
        If Uri.TryCreate(strUrl, UriKind.Relative, UriOut) Then
            'yes
            Debug.Print(UriOut.ToString & " is Relative")
        Else
            'no
            Debug.Print(strUrl & " is not Relative")
        End If
 
        'same as above, but this time with a string that is Relative
        strUrl = "/index.aspx"
        If Uri.TryCreate(strUrl, UriKind.Absolute, UriOut) Then
            Debug.Print(UriOut.ToString & " is absolute")
        Else
            Debug.Print(strUrl & " is not absolute")
        End If
 
        If Uri.TryCreate(strUrl, UriKind.Relative, UriOut) Then
            Debug.Print(UriOut.ToString & " is Relative")
        Else
            Debug.Print(strUrl & " is not Relative")
        End If
    End Sub
    Sub TryCreate3()
        'demonstrates Uri.TriCreate(Uri,Uri,Uri)
        'concatonates the first two URIs into the third
 
        'get a base uri
        Dim BaseUri As Uri = New Uri("http://devshed.us/")
 
        'note that we have to specify the urikind
        Dim RelativeUri As New Uri("/links.aspx", UriKind.Relative)
 
        'placeholder for the return val
        Dim UriOut As Uri = Nothing
 
        'add the two together
        If Uri.TryCreate(BaseUri, RelativeUri, UriOut) Then
            Debug.Print(UriOut.ToString)
        Else
            Throw New Exception("Invalid URI")
        End If
 
    End Sub
 
End Module
 

More ...

Tools > Options

steve@4penny.net — Tue, 15 Mar 2011 13:08:34 GMT

I spend most of my day in either SMSS or Visual Studio (currently 2010), and there are a couple of small changes that I’m fond of making. It’s not a big deal, but I really like VS to close the quote marks for me in the HTML editor, it makes typing slightly faster. And, I like the tabs on the tab well to be all the same size. It’s slightly easier to close a bunch of them quickly, you don’t have to move the cursor, you can just click.

But, I hate to spend the time to look for these options in Tools > Options, there are so many options. So I thought I’d blog the options and have them on hand the next time I need to set them.

In order to get the ‘tabs’ feature, you’ll want to install the Productivity Power Pack

(click to enlarge)

Here is the ‘tab’ settings

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Creating a DataTable dynamically

steve@4penny.net — Mon, 21 Feb 2011 20:40:12 GMT

This is a short example on how to create a DataTable dynamically, assign a primary key to it, and then how to update it

You can search a data table with or without a primary key, but if you don’t use the key you’ll get back an array of rows; in this case the single row is really what we need.

This code is very useful for submitting samples to vendors, you don’t have to fake data connections.

There is no error checking, this is just template code.

Code Snippet
 Function GetDataTable() As DataTable
    Dim oDT As New DataTable
    Dim oKeys(0) As DataColumn
    'create a data table to use as our input source
 
    'create columns 
    Dim oCol As DataColumn = New DataColumn("order", System.Type.GetType("System.String"))
    oDT.Columns.Add(oCol)
    oKeys(0) = oCol
    oDT.Columns.Add(New DataColumn("salesperson", System.Type.GetType("System.String")))
    oDT.Columns.Add(New DataColumn("amount", System.Type.GetType("System.Double")))
    oDT.PrimaryKey = oKeys
 
    'create the rows 
    oDT.Rows.Add("ORD00100", "Bob@test.com", 1.23)
    oDT.Rows.Add("ORD00102", "Bob@test.com", 3.23)
    oDT.Rows.Add("ORD00104", "Sam@test.com", 2.23)
    oDT.Rows.Add("ORD00105", "Sam@test.com", 4.23)
 
    Return oDT
 
End Function
 
Sub updateDataTable(ByVal strOrder As String, ByVal dblAmount As Double)
    Dim oRow As DataRow
 
    '"order" is our primary key. Search the primary key for strOrder
    oRow = oDT.Rows.Find(strOrder)
 
    'in the row found, set the Amount column
    oRow("amount") = dblAmount
 
    'save
    oDT.AcceptChanges()
 
End Sub
 

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Enterprise Library 5.0 Data Access Application Block (DAAB) starter

steve@4penny.net — Fri, 17 Dec 2010 16:19:03 GMT

Every time I add the DAAB to an application, I struggle a little with which .dlls to add to my project.

So, here it a walk through to get you (and me) started.

Download and install the Enterprise Library 5.0 objects. Choose the larger install, the second one.

Create a project, and set a reference to these dlls:

Microsoft.Practices.EnterpriseLibrary.Common.dll
Microsoft.Practices.EnterpriseLibrary.Data.dll
Microsoft.Practices.ServiceLocation.dll

That should do it.

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StoredProcedure Class

steve@4penny.net — Thu, 09 Dec 2010 21:16:35 GMT

This is the class that I use to abstract the Enterprise Library DAAB. There are other classes, found here

Code Snippet

Imports Microsoft.VisualBasic
Imports System.Data.SqlClient
Imports System.Data
Imports Microsoft.Practices.EnterpriseLibrary.Data
Imports Microsoft.Practices.EnterpriseLibrary.Data.Sql
Imports System.Configuration
 
Public Class storedProcedure
    Dim _storedProcName As String
    Dim _db As String
    Public commandParameters As System.Collections.Generic.List(Of commandParameter)
    Public CommandTimeout As Int16
    Dim cs As New Dictionary(Of String, String)
 
    Sub New(ByVal StoredProcName As String, ByVal db As String)
        _storedProcName = StoredProcName
        _db = db.ToUpper
        commandParameters = New System.Collections.Generic.List(Of commandParameter)
 
        cs.Add("NGB01", "Data Source=ngb-sql-05;User Id=4pennyapp;Password=app4me;Initial Catalog=NGB01")
        cs.Add("ELSTN", "Data Source=ngb-sql-05;User Id=4pennyapp;Password=app4me;Initial Catalog=ELSTN")
        cs.Add("NGBOED", "Data Source=ngb-sql-05;User Id=4pennyapp;Password=app4me;Initial Catalog=NGBOED")
        cs.Add("STONE", "Data Source=ngb-sql-05;User Id=4pennyapp;Password=app4me;Initial Catalog=STONE")
        cs.Add("INTRANET2", "Data Source=ngb-sql-05;User Id=4pennyapp;Password=app4me;Initial Catalog=Intranet2")
        cs.Add("TWO", "Data Source=vmGP11;User Id=4pennyapp;Password=app4me;Initial Catalog=TWO")
    End Sub
 
    Function execute(ByVal timeout As Int32, ByRef cps As System.Collections.Generic.List(Of commandParameter)) As Int32
        Dim strError As String = ""
        Try
 
            Dim aParams As SqlParameter() = Nothing
            Dim a As Int16 = 0
 
            Dim db As Database
            db = New SqlDatabase(cs(_db))
 
            Dim dbCommand As Common.DbCommand = db.GetStoredProcCommand(_storedProcName)
 
            If timeout > 0 Then
                dbCommand.CommandTimeout = timeout
            End If
 
            For Each cp As commandParameter In commandParameters
                Select Case cp.ParamDirection
                    Case ParameterDirection.Input
                        db.AddInParameter(dbCommand, cp.ParamName, cp.ParamType, cp.ParamValue)
                    Case ParameterDirection.InputOutput
                        'not handled
                    Case ParameterDirection.Output
                        db.AddOutParameter(dbCommand, cp.ParamName, cp.ParamType, cp.ParamSize)
                    Case ParameterDirection.ReturnValue
                        'not handled
                End Select
            Next
            db.AddParameter(dbCommand, "@ReturnValue", DbType.Int32, ParameterDirection.ReturnValue, String.Empty, System.Data.DataRowVersion.Default, 0)
 
            db.ExecuteNonQuery(dbCommand)
            For Each cp As commandParameter In commandParameters
                cp.ParamValue = db.GetParameterValue(dbCommand, cp.ParamName)
            Next
 
            Dim rcp As commandParameter
            rcp = New commandParameter("@Return_Value", 0, DbType.Int16)
            rcp.ParamValue = db.GetParameterValue(dbCommand, "@ReturnValue")
            commandParameters.Add(rcp)
 
            cps = commandParameters
            Return rcp.ParamValue
        Catch ex As Exception
            strError = "query: " & _storedProcName & "
"
            For Each cp As commandParameter In commandParameters
                strError += "params: " & cp.ParamName & " = " & cp.ParamValue.ToString & "
"
            Next
 
            ex.Source = strError
            Throw ex
 
        End Try
 
    End Function
    Function execute() As Int32
        Dim intTimeout As Int32 = -1
        Dim cp As New System.Collections.Generic.List(Of commandParameter)
        Return execute(intTimeout, cp)
    End Function
    Function execute(ByRef cp As System.Collections.Generic.List(Of commandParameter)) As Int32
        Dim intTimeout As Int32 = -1
        Return execute(intTimeout, cp)
    End Function
 
    Function executeScalar() As Object
        Dim strError As String = ""
        Try
 
            Dim aParams As SqlParameter() = Nothing
            Dim a As Int16 = 0
            Dim db As Database '= DatabaseFactory.CreateDatabase(_db)
            db = New SqlDatabase(cs(_db))
            Dim dbCommand As Common.DbCommand = db.GetStoredProcCommand(_storedProcName)
            For Each cp As commandParameter In commandParameters
                db.AddInParameter(dbCommand, cp.ParamName, cp.ParamType, cp.ParamValue)
            Next
 
            Return db.ExecuteScalar(dbCommand)
        Catch ex As Exception
            strError = "query: " & _storedProcName & "
"
            For Each cp As commandParameter In commandParameters
                strError += "params: " & cp.ParamName & " = " & cp.ParamValue.ToString & "
"
            Next
            strError += ex.Message
            Throw New Exception(strError)
 
        End Try
 
        executeScalar = Nothing
    End Function
    Function getReader(ByVal timeout As Int32) As SqlDataReader
        Dim strError As String = ""
        Try
 
            Dim aParams As SqlParameter() = Nothing
            Dim a As Int16 = 0
            Dim db As Database '= DatabaseFactory.CreateDatabase(_db)
            db = New SqlDatabase(cs(_db))
            Dim dbCommand As Common.DbCommand = db.GetStoredProcCommand(_storedProcName)
            If timeout > 0 Then
                dbCommand.CommandTimeout = timeout
            End If
            For Each cp As commandParameter In commandParameters
                db.AddInParameter(dbCommand, cp.ParamName, cp.ParamType, cp.ParamValue)
            Next
 
            Return db.ExecuteReader(dbCommand)
        Catch ex As Exception
            strError = "query: " & _storedProcName & "
"
            For Each cp As commandParameter In commandParameters
                strError += "params: " & cp.ParamName & " = " & cp.ParamValue.ToString & "
"
            Next
 
            ex.Source = strError
            Throw ex
 
        End Try
        getReader = Nothing
 
    End Function
    Function getReader() As SqlDataReader
        getReader = getReader(-1)
 
    End Function
    Function getTable() As DataTable
        getTable = getTable(-1)
    End Function
 
    Function getTable(ByVal timeout As Int32) As DataTable
        Dim strError As String = ""
        Try
 
            Dim aParams As SqlParameter() = Nothing
            Dim a As Int16 = 0
 
            Dim db As Database
            db = New SqlDatabase(cs(_db))
 
            Dim dbCommand As Common.DbCommand = db.GetStoredProcCommand(_storedProcName)
 
            'set the command timeout
            If timeout > 0 Then
                dbCommand.CommandTimeout = timeout
            End If
 
            For Each cp As commandParameter In commandParameters
                db.AddInParameter(dbCommand, cp.ParamName, cp.ParamType, cp.ParamValue)
            Next
 
            Return db.ExecuteDataSet(dbCommand).Tables(0)
        Catch ex As Exception
            strError = "query: " & _storedProcName & "
"
            For Each cp As commandParameter In commandParameters
                If Not cp.ParamValue Is Nothing Then
                    strError += "params: " & cp.ParamName & " = " & cp.ParamValue.ToString & "
"
                Else
                    strError += "params: " & cp.ParamName & " = Nothing
"
                End If
            Next
 
            ex.Source = strError
            Throw ex
        End Try
        getTable = Nothing
 
    End Function
 
End Class

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SmartXLS

steve@4penny.net — Thu, 23 Sep 2010 14:52:08 GMT

I’m testing a product called SmartXLS, here’s my first stab at a class to use it’s properties

Imports SmartXLS
Imports System.IO

Public Class SmartXLS
    Dim wb As New WorkBook
    ''' zero based
    Public Columns As Int16
    ''' zero based
    Public Rows As Int16

    ''' 
    ''' Creates a new instance of the SmartXML class
    ''' 
    ''' Excel FileName, includes the fill path
    ''' 
    Sub New(ByVal strFileName As String)
        Dim strExt As String = Path.GetExtension(strFileName)

        Select Case strExt.ToUpper
            Case ".XLS"
                wb.read(strFileName)
            Case ".XLSX"
                wb.readXLSX(strFileName)
            Case Else
                Throw New Exception("Invalid file name")
        End Select

        Columns = wb.LastCol
        Rows = wb.LastRow

    End Sub

    ''' 
    ''' To Read an Excel File and return a Generic List of the column headers
    ''' 
    ''' A Generic List of String values
    Public Function GetExcelColumnHeaders() As List(Of String)
        Dim oColumnHeaders As New List(Of String)
        Dim Dt As New DataTable()

        Try

            Dim i As Int32
            For i = 0 To Columns
                oColumnHeaders.Add(wb.getFormattedText(0, i))
            Next

            Return oColumnHeaders
        Catch ex As Exception
            Throw ex
        End Try

    End Function

    ''' 
    ''' To Read an Excel File and Get a DataTable with its values
    ''' 
    ''' A DataTable with Excel Values
    ''' 
    Public Function GetExcelAsDataTable() As DataTable

        Dim Dt As New DataTable()

        Dim c As Integer = 0
        Dim r As Integer = 0

        'add the correct number of columns to our datatable
        For c = 0 To Columns
            Dt.Columns.Add(GetExcelColumnHeaders(c))
        Next

        'skip the first row
        For r = 1 To Rows
            Dim dr As DataRow = Dt.NewRow

            For c = 0 To Columns
                dr(c) = (wb.getFormattedText(r, c))
            Next
            Dt.Rows.Add(dr)

        Next

        Return Dt
    End Function

End Class

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Decorate (document) a class in VB.NET

steve@4penny.net — Thu, 23 Sep 2010 14:02:12 GMT

I ran across a technique that I’ve not used before (you learn something new every day, don’t you?) that I want to document here. It involves decorating a class so that the methods and properties show up in VB when you call the class.

Basically, you just add comments above the methods like this:

    ''' 
    ''' Creates a new instance of the ExcelHelper class
    ''' 
    ''' Excel File as Stream
    Public Sub New(ByVal strFile As String)
        myWorkbook = SpreadsheetDocument.Open(strFile, False)
        workbookpart = myWorkbook.WorkbookPart
        worksheetPart = workbookpart.WorksheetParts.FirstOrDefault()
        stringTablePart = workbookpart.SharedStringTablePart
        columns = GetExcelColumns()
    End Sub

And when you call the class, you can see the documentation:

Nice, right?

The following XML comment tags are officially supported in VB.NET: c,code, example, exception, include, list, para, param, paramref, permission, remarks, returns, see, seealso, summary and typeparam.

c: This tag is used to denote code, so it can be used to identify sample code associated with a particular entity within the source code. Note that the tag can only be used to represent a single line of code or to denote that some of the text on a line should be marked up as code. Example: Dim MyObject As MyType

code: This tag is used to denote more than one line of code, so it can be used to identify longer areas of sample code.

example: This tag may be used to describe an example of using a particular method or class. It is possible to include code samples within the example tag by making use of either the c or code tags.

exception: The exception tag allows a method's exception handling to be documented. The cref attribute allows the namespace of the exception handler to be included. Example: Throws an exception if the customer is not found.

include: This tag allows documentation to be imported from an external XML file rather than being stored within the source code itself. As such it may be useful if the documentation is written by people other than the software developers (e.g. technical writers).

list: This tag allows bulleted or numbered lists or tables to be added to XML comments.

para: This tag indicates that the text within the tags should be formatted within a paragraph. As such it can be used to format text within other tags such as summary or returns. Example: This is a paragraph

param: The param tag is used to document a method's arguments. The tag's name attribute specifies the name of the argument to which the tag refers. The tag is also used by Visual Studio's Intellisense system to show a description of a method's arguments. It is also used by the Visual Studio Object Browser. Example: The filename of the file to be loaded.

paramref: This tag can be used to refer to a method's argument elsewhere within the method's XML comments. The tag's name attribute specifies the name of the argument to which the tag refers. Note that the param tag is actually used to describe the parameter. Example: Use the argument to specify which filename is loaded.

permission: The permission tag can be used to describe any special permissions a specific object needs. The object to which the permission refers is included as the cref attribute. Example: Class needs to write to the file system, ensure user has appropriate access.

summary: The summary tag describes a method or class, so it is the most important tag. As well as being used in a project's documentation, the tag is also used by Visual Studio's Intellisense system to show a description of the method or class being referenced. It is also used by the Visual Studio Object Browser.

remarks: The remarks tag can be used to supply additional information about a method or class, supplementing the details given in the summary tag. As with the summary tag, this tag is also used by Visual Studio's Intellisense system and the Visual Studio Object Browser.

returns: Describes the return value of a method. Example: True if user has permission to access the resource, otherwise False.

see: The see tag is used to reference other entities (such as classes) in the project. The see tag is intended for use within other tags such as the summary tag. Example:

seealso: The seealso tag resembles the see tag and has identical syntax, except that the text is intended to be used to create a separate seealso section for the entity's documentation.

typeparam: Typeparam is used in an identical way to param, except that it is used to document a type associated with a generic class or function.

value: Value is only used when documenting a property, and is used to describe the value assigned to that. The comment is not required for properties that are marked as read only. Example: Sets the employee's salary

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