Is it possible to obtain the content of a variable by referencing to its name.
I have a bunch of variables like
Dim _tipoEntero As String = "^[0-9].$"
Dim _tipoTelefono As String = "^[0-9]{6}$"
and I'm trying to reference as something like
myValue = GetVariableValue("_tipo" + validationString)
You could use a Dictionary.
Dim tipos As New Dictionary(Of String, String)
tipos.Add("Entero", "^[0-9].$")
tipos.Add("Telefono", "^[0-9]{6}$")
myValue = tipo(validationString)
The short answer for your question is "Yes" it is possible :
myValue = Me.GetType.GetField("_tipo" & validationString).GetValue(Me)
And we can make more effective :
myValue = Me.GetType.GetField("_tipo" & validationString, Reflection.BindingFlags.NonPublic Or Reflection.BindingFlags.Instance Or Reflection.BindingFlags.Public Or Reflection.BindingFlags.IgnoreCase).GetValue(Me)
I set the binding flags to catch both public and private variables, and also ignoring the case sensitive of your search, so it doesn't matter you type "_tipo" or "_TiPo".
This is an answer for your question, but I didn't suggest you a better way to do your task.
Related
I have a large string over 500 char which is called strEssay. I want to use a function(since I will need to look for several patterns) to return two values if (for example the name) Frank is found or not.
This is the function I'm trying to use:
Function NameFinder(strEssay as String, strName as String)
Dim varNameCounter as Variant
Dim strNameFinderResult as String
varNameCounter = 0
strNameFinderResult = ""
If strEssay like "*" & strName & "*" Then
strNameFinderResult = strName
varNameFinderCounter = 1
Else
strNameFinderResult = ""
varNameFinderCounter = .001
EndIf
End Function
I want to be able to return back to my subroutine both 'strNameFinderResult' and 'varNameFinderCounter'.
Is there any way that I can return both values?
If I can't return both simultaneously can I return one through the function and the other through a textbox or something? What would calling the function look like in the subroutine and/or how would I need to change my function?
NameFinder() function, returning array of 3 elements. It is called and returned by TestMe(), writing the following to the console:
Function NameFinder(essay As String, name As String)
Dim nameFinderResult As String
Dim namefinderCounter As String
nameFinderResult = "" & essay & name
namefinderCounter = 0.001 + 12
NameFinder = Array(nameFinderResult, namefinderCounter, "something else")
End Function
Public Sub TestMe()
Dim myArray As Variant
myArray = NameFinder("foo", "bar")
Dim i As Long
For i = LBound(myArray) To UBound(myArray)
Debug.Print myArray(i)
Next i
End Sub
As a general rule, you have to give the routine a type like this:
Function NameFinder(strEssay as String, strName as String) as string
But, that returns only ONE value.
So, a function (as opposed to a sub) returns one value (as a general rule).
However, you CAN also return parameters that you pass. I mean, in above, you can't make TWO assignments to one variable, can you?
So, you can use a Sub like this:
Sub NameFinder(strEssay as String, strName as String, _
strNameFinderResult as string, _
varNameFinderCounter as double)
If strEssay like "*" & strName & "*" Then
strNameFinderResult = strName
varNameFinderCounter = 1
Else
strNameFinderResult = ""
varNameFinderCounter = .001
EndIf
So in code, you now can go:
dim strMyResult as string
dim strFinderCount as Double
Call NameFinder("MyEassy", "Joe Blow", strMyResult, strFinderCount)
So, you can return values with the parameters.
Now, I suppose it possible for some strange reason, that you want to use a function to return two values with a single assignment?
What you would do is this in your code module.
Define a custom type, and use that.
eg this:
Option Compare Database
Option Explicit
Type SearchResult
strName As String
FindCount As Double
End Type
Function NameFinder(strEssay As String, strName As String) As SearchResult
NameFinder.FindCount = 0
NameFinder.strName = ""
If strEssay Like "*" & strName & "*" Then
NameFinder.strName = strName
NameFinder.FindCount = 1
Else
NameFinder.strName = ""
NameFinder.FindCount = 0.001
End If
End Function
So, now to use in code? You can go like this:
dim MyResults as SearchResult
MyResults = NameFinder("My eassy", "Joe Blow")
debug.print "Name found result = " & MyResults.strName
debug.print "Count of find = " & MyResult.FindCount
The VERY nice thing about above is you get full intel-sense in your code editor.
eg this:
So by building a custom data type, you can use "one" assignment for the return type. And you get nice type checking and inteli-sense in the VBA code editor.
And you can even do this:
But, to get both variables, then you would in theory wind up calling the function two times. So, you can actually use the function without declarer of variables like this:
Debug.Print NameFinder("MyEassy", "Joe blow").strName
Debug.Print NameFinder("MyEassy", "Joe blow").FindCount
So, I don't recommend the above, but in the case in which you ONLY want one of the return values, then the raw expression (function) like above would be a use case (and no need to even declare a return variable).
But, without a doubt, define a custom type in code as per above. The reason is now you get a really nice VBA editor type-checking, inteli-sense, and also that you only have to declare "one" variable that holds two values.
In fact, the results are very much like JavaScript, or even c# in which you declare a "class" type. So with a custom "type" you are declaring a data type of your own. And the beauty of this is if you need say 3 values, then once again you create a type with 3 "inside" values.
The you ONLY have to declare that one variable as the custom type.
With this you get:
Very valuable compile time syntax and data type checking of the var types you are using.
You get GREAT VBA inteli-sense while coding - which means less coding mistakes.
And you type far less typing in the VBA editor as it will pop-up the choices for you as you write code. And you can't type or choose the wrong sub - type, as the compiler will catch this.
I'm trying to pass a dynamic amount of variables to a Sub by using ByRef;
Essentially I'm trying to create a module that I can easily import into my projects and make handling the file saving/loading process automated.
The Sub/Function would take a number of variables as references and then loop through them changing each one's value.
I realize I'm missing a crucial point in how visual basic's syntax works but I haven't been able to figure out what I need to do.
The code I've written for this is:
Public Sub LoadSaveToVars(ByRef KeyNamesAndVars() As Object, ByVal FileLoc As String = "")
If isEven(KeyNamesAndVars.Length) Then
Dim Contents As String = My.Computer.FileSystem.ReadAllText(FileLoc)
Dim isOnName As Boolean = True
Dim CurrentVal As String = ""
For i = 0 To KeyNamesAndVars.Length - 1
If isOnName Then
CurrentVal = GetStringValue(KeyNamesAndVars(i), Contents) 'Get the value of the key with the key name in the array
isOnName = False
Else
KeyNamesAndVars(i) = CurrentVal 'Set the variable referenced in the array to the value
isOnName = True
End If
Next
Else
Throw New ArgumentOutOfRangeException("The key names and variables supplied are not even.", "Error loading to variables!")
End If
End Sub
And here's how I try to use this function:
Dim TestVar1 As String = ""
Dim TestVar2 As String = ""
LoadSaveToVars({"key1", TestVar1, "key2", TestVar2})
To keep this question clean I did not include the other functions, but I did make a poor attempt at drawing what I want to happen: https://gyazo.com/eee34b8dff766401f73772bb0fef981a
In the end, I want TestVar1 to be equal to "val1" and TestVar2 to be equal to "val2" and to be able to extend this to a dynamic number of variables. Is this possible?
Is it possible to obtain the content of a variable by referencing to its name.
I have a bunch of variables like
Dim _tipoEntero As String = "^[0-9].$"
Dim _tipoTelefono As String = "^[0-9]{6}$"
and I'm trying to reference as something like
myValue = GetVariableValue("_tipo" + validationString)
You could use a Dictionary.
Dim tipos As New Dictionary(Of String, String)
tipos.Add("Entero", "^[0-9].$")
tipos.Add("Telefono", "^[0-9]{6}$")
myValue = tipo(validationString)
The short answer for your question is "Yes" it is possible :
myValue = Me.GetType.GetField("_tipo" & validationString).GetValue(Me)
And we can make more effective :
myValue = Me.GetType.GetField("_tipo" & validationString, Reflection.BindingFlags.NonPublic Or Reflection.BindingFlags.Instance Or Reflection.BindingFlags.Public Or Reflection.BindingFlags.IgnoreCase).GetValue(Me)
I set the binding flags to catch both public and private variables, and also ignoring the case sensitive of your search, so it doesn't matter you type "_tipo" or "_TiPo".
This is an answer for your question, but I didn't suggest you a better way to do your task.
I have a ListBox that is populated with my entity names, i.e. A1AllocationHelp1Entity
On select I need to pass that string name to get an EntityBase2 type.
I can get it using reflection:
Public Function CreateEntity(ByVal entityName As String) As EntityBase2
Dim myAssembly = Assembly.LoadFrom(DALFileName)
Dim assemblyName = Split(dynamicAssembly.FullName, ",")(0)
Dim myEntityName = assemblyName & ".EntityClasses." & entityName
Dim handle = Activator.CreateInstance(assemblyName, myEntityName)
Dim entity = CType(handle.Unwrap(), EntityBase2)
Return entity
End Function
but if I have the types there that llblgen generates, I would like to be able to instantiate it somehow without resorting to reflection.
Is there any way I can do that?
All that refection code can be replaced with a single line
Return GeneralEntityFactory.Create( _
CType(System.Enum.Parse(GetType(EntityType), entityName), EntityType))
This returns the same type and is the answer I was looking for.
I am refactoring some legacy code. The app was not using querystrings. The previous developer was hard coding some variables that the app uses in other places.
Like this using VB.NET
so.Cpage = "ContractChange.aspx"
My question is can I programatically set this value and include the current querystring?
I want so.Cpage to be something like ContractChange.aspx?d=1&b=2
Can I do this with the request object or something? Note, I don't need the domain.
To get the current query string you would simply do something like the following:
Dim query as String = Request.QueryString("d")
This will assign the value of the "d" querystring to the string variable "query". Note that all query string values are strings, so if you're passing numbers around, you'll need to "cast" or convert those string values to numerics (be careful of exceptions when casting, though). For example:
Dim query as String = Request.QueryString("d")
Dim iquery as Integer = CType(query, Integer)
The QueryString property of the Request object is a collection of name/value key pairs. Specifically, it's of type System.Collections.Specialized.NameValueCollection, and you can iterate through each of the name/value pairs as so:
Dim coll As System.Collections.Specialized.NameValueCollection = Request.QueryString
Dim value As String
For Each key As String In coll.AllKeys
value = coll(key)
Next
Using either of these mechanisms (or something very similar) should enable you to construct a string variable which contains the full url (page and querystrings) that you wish to navigate to.
Try this:
so.Cpage = "ContractChange.aspx?" & Request.RawUrl.Split("?")(1)
In VB.Net you can do it with the following.
Dim id As String = Request.Params("RequestId")
If you want to process this in as an integer, you can do the following:
Dim id As Integer
If Integer.TryParse(Request.Params("RequestId"), id) Then
DoProcessingStuff()
End If
try this
Dim name As String = System.IO.Path.GetFileName(Request.ServerVariables("SCRIPT_NAME"))
Dim qrystring As String = Request.ServerVariables("QUERY_STRING")
Dim fullname As String = name & "/" & qrystring
Not sure about the syntax in VB.NET but in C# you would just need to do
StringId = Request.QueryString.Get("d");
Hope this helps.