I'm trying to create an array of strings. In the watches window, it always says that the value of my array items are "", instead of the values I typed.
I tried to find answers online but none of them fixed my problem. Is there anything wrong with my code?
Thanks!
Dim fish18(0 To 2) As String
fish18(0) = "$I$5"
fish18(1) = "$I$9"
fish18(2) = "$I$10"
Check your values in the Locals window.
In VBE: View > Locals Window > Expand on Array (fish18)
Dim fish18(2) As String
fish18(0) = "$I$5"
fish18(1) = "$I$9"
fish18(2) = "$I$10"
Related
What is VB.Net code to filter a String Array ?
I use following code
Imports System.Reflection
Dim ass As Assembly = Assembly.GetExecutingAssembly()
Dim resourceName() As String = ass.GetManifestResourceNames()
that return a String array
How can I filter resourceName() variable ?
I tried following lines of code
Dim sNameList() As String
= resourceName.FindAll(Function(x As String) x.EndsWith("JavaScript.js"))
but compiler return following error
BC36625: Lambda expression cannot be converted to 'T()' because 'T()' is not a delegate type
How can I correct this error ?
Is there another solution to solve my problem ?
Dim sNameList = resourceName.Where(Function(s) s.EndsWith("JavaScript.js"))
In that case, sNameList is an IEnumerable(Of String), which is all you need if you intend to use a For Each loop over it. If you genuinely need an array:
Dim sNameList = resourceName.Where(Function(s) s.EndsWith("JavaScript.js")).ToArray()
The reason that your existing code didn't work is that Array.FindAll is Shared and so you call it on the Array class, not an array instance:
Dim sNameList = Array.FindAll(resourceName, Function(s) s.EndsWith("JavaScript.js"))
If I have a string "cboEnoughMoney(0)", is it possible to retrieve the control from a control array that I have in my form, cboEnoughMoney?
In my code, I try to refer to the control in this way:
frm.Controls(sControlName).ListIndex = -1
sControlName in this case is "cboEnoughMoney(0)" and I get an error that the control was not found.
EDIT: One of the issue's i'm having is trying to as above set the .listindex to -1, another one is where I actually try to get and set value to the combobox. In a function - i pass form name as parameter called frm.
In the code what has been done is this....
dim ctlData as string
If Frm.Controls(RS!CTRLname).ListIndex > 0 Then
CtlData = Frm.Controls(RS!CTRLname).Value
Else
CtlData = ""
End If
Any idea how I'd be able to do that with cboEnoughMoney(0)....
I assume I could follow your example and check
if instr(1,RS!CTRLname, "(")
but if there is, how would I refer to that particular control in frm
It is just enough to look in the VB Properties Window: if you search "cboEnoughMoney(0)" you will find "cboEnoughMoney"(0) (without double quotes). Still the name is the same as a non-array control.
So, it is perfectly legal to refer to a VB Control with Name and Index, no need for a controls loop here:
If isControlsArray Then
Set ctrl = Me.Controls(Name)(Index) '// array
Else
Set ctrl = Me.Controls(Name) '// non array
End If
You cannot use the (index) part in a lookup via .Controls.
You can loop them manually & given that you can safely assume any control name with a ( is an array member and thus will have an Index property match on that:
Private Function GetControl(ByVal name As String) As VB.Control
Dim pos As Long: pos = InStr(name, "(")
If pos = 0 Then
Set GetControl = Me.Controls(name) '// non array
Else
Dim index As Long
index = Val(Mid$(name, pos + 1)) '// get index #
name = Left$(name, pos - 1) '// get base name
For Each GetControl In Me.Controls
If (GetControl.name = name) Then
If (GetControl.index = index) Then Exit Function
End If
Next
Set GetControl = Nothing
End If
End Function
And then:
GetControl("cboEnoughMoney(1)").ListIndex = -1
I'm trying to use the values inside of a Variant.
An example of the code:
Dim Holder as Variant
Holder = "1,1,1,1,1"
Later I will be using this Variant inside of an Array().
The Declaration is like this:
.TextFileColumnDataTypes = Array(Holder)
There was an error right after this
Run-Time Error '5':
Invalid Procedure call or argument*
Is there a way to insert the Variant's values into Array(<Here?).
Holder's value is not constant, it will change depending on a function I created.
A way to accomplish this is as suggested in comments, using the split
If you are getting an error I am guessing that you are not using it correctly.
This is how the code should look.
dim i as long
dim var
Holder = "1,1,1,1,1"
var = Split(Holder,",")
for i = 0 to 4
.TextFileColumnDataTypes = var(i)
next i
I am not able to create an array in VB 6.0 and I'm going crazy trying to figure it out. First of all VB is not my native language, I am a PHP programmer so arrays are not a new concept for me... Hopefully someone can help with this.
This is my function:
Function get_plant() As String
Dim arrPlant(1 To 10) As String
arrPlant(1) = "PL1"
arrPlant(2) = "PL2"
arrPlant(3) = "PL3"
arrPlant(4) = "PL4"
arrPlant(5) = "PL5"
arrPlant(6) = "PL6"
arrPlant(7) = "PL7"
arrPlant(8) = "PL8"
arrPlant(9) = "PL9"
arrPlant(10) = "PL0"
get_plant = arrPlant
End Function
Then I tried calling it with this (and about 10 other variations...):
Dim plant_code() As String
plant_code = get_plant()
MsgBox plant_code(1)
When I try and use the array I get this:
Question mark in the array index
What the heck am I missing here?
The return type of the function you have given is string not string() and you are trying to return string array. Try giving this
Function get_plant() As String()
I'm new to F# and trying to dive in first and do a more formal introduction later. I have the following code:
type Person =
{
Id: int
Name: string
}
let GetPeople() =
//seq {
use conn = new SQLiteConnection(connectionString)
use cmd = new SQLiteCommand(sql, conn)
cmd.CommandType <- CommandType.Text
conn.Open()
use reader = cmd.ExecuteReader()
let mutable x = {Id = 1; Name = "Mary"; }
while reader.Read() do
let y = 0
// breakpoint here
x <- {
Id = unbox<int>(reader.["id"])
Name = unbox<string>(reader.["name"])
}
x
//}
let y = GetPeople()
I plan to replace the loop body with a yield statement and clean up the code. But right now I'm just trying to make sure the data access works by debugging the code and looking at the datareader. Currently I'm getting a System.InvalidCastException. When I put a breakpoint at the point indicated by the commented line above, and then type in the immediate windows reader["name"] I get a valid value from the database so I know it's connecting to the db ok. However if I try to put reader["name"] (as opposed to reader.["name"]) in the source file I get "This value is not a function and cannot be applied" message.
Why can I use reader["name"] in the immediate window but not in my fsharp code? How can I use string indexing with the reader?
Update
Following Jack P.'s advice I split out the code into separate lines and now I see where the error occurs:
let id = reader.["id"]
let id_unboxed = unbox id // <--- error on this line
id has the type object {long} according to the debugger.
Jack already answered the question regarding different syntax for indexing in F# and in the immediate window or watches, so I'll skip that.
In my experience, the most common reason for getting System.InvalidCastException when reading data from a database is that the value returned by reader.["xyz"] is actually DbNull.Value instead of an actual string or integer. Casting DbNull.Value to integer or string will fail (because it is a special value), so if you're working with nullable columns, you need to check this explicitly:
let name = reader.["name"]
let name_unboxed : string =
if name = DbNull.Value then null else unbox name
You can make the code nicer by defining the ? operator which allows you to write reader?name to perform the lookup. If you're dealing with nulls you can also use reader?name defaultValue with the following definition:
let (?) (reader:IDataReader) (name:string) (def:'R) : 'R =
let v = reader.[name]
if Object.Equals(v, DBNull.Value) then def
else unbox v
The code then becomes:
let name = reader?name null
let id = reader?id -1
This should also simplify debugging as you can step into the implementation of ? and see what is going on.
You can use reader["name"] in the immediate window because the immediate window uses C# syntax, not F# syntax.
One thing to note: since F# is much more concise than C#, there can be a lot going on within a single line. In other words, setting a breakpoint on the line may not help you narrow down the problem. In those cases, I normally "expand" the expression into multiple let-bindings on multiple lines; doing this makes it easier to step through the expression and find the cause of the problem (at which point, you can just make the change to your original one-liner).
What happens if you pull the item accesses and unbox calls out into their own let-bindings? For example:
while reader.Read() do
let y = 0
// breakpoint here
let id = reader.["id"]
let id_unboxed : int = unbox id
let name = reader.["name"]
let name_unboxed : string = unbox name
x <- { Id = id_unboxed; Name = name_unboxed; }
x