I have the following function, designed to walk through XML and create a linear structure of all nodes:
function get_children(n)
if n.hasChildNodes() then
for each child in n.childNodes
set local_array = array_merge(get_children(child), local_array)
next
else
set local_array = Array(n)
end if
get_children = local_array
end function
I've tried a ton of variations, but I keep getting errors on the line
set local_array = Array(n)
It it's current form, I see:
Error Type:
Microsoft VBScript runtime (0x800A01A8)
Object required
/_inc/nav/left-nav.inc, line 37
Am I mis-using the Array() construct? Aren't I able to create an array with a single value?
Change
set local_array = Array(n)
to
local_array = Array(0)
set local_array(0) = n
Related
I need to "return" an Array of Objects from a function that I created using VBA. When I try to set the function as the array it gives me an error message, saying
Object is required.
I am not very used to VBA, and I can't fix this. Here is the function code:
Function sortedList(listRange As Integer, tempList() As ship) As ship
Dim temp As ship
Set temp = Nothing
For i = listRange - 10 To 1 Step -1
For j = 2 To listRange - 10
If tempList(j - 1).Arrival > tempList(j).Arrival Then
Set temp = tempList(j - 1)
Set tempList(j - 1) = tempList(j)
Set tempList(j) = temp
End If
Next j
Next i
'return tempList - how?
Set sortedList = tempList
End Function
Ship is a "class" that I created. tempList is the array of objects from class ship that I need to return from the function sortedList.
The function works, it's just the return part that I can't make work.
Thanks for the help. If more information is necessary let me know!
Declare the function to return an array
Function sortedList(listRange As Integer, tempList() As ship) As ship()
and then assign the result without Set
sortedList = tempList
For some reason the countries that seem to be returned are all returning in pairs? How can you change the code so it only returns the countries in 'Europe' once?
function newcountry(continent,country)
local object = {}
object.continent = continent
object.country = country
local list = {}
for i in pairs( object ) do
if object.continent == "Europe" then
table.insert(list, object.country)
print(object.country)
end
end
return object
end
a = newcountry("Africa","Algeria")
b = newcountry("Europe","England")
c = newcountry("Europe","France")
d = newcountry("Europe","Spain")
e = newcountry("Asia","China")
I'm not sure what you are trying to accomplish with this code, but to answer your question:
function newcountry(continent,country)
local object = {}
object.continent = continent
object.country = country
local list = {}
if object.continent == "Europe" then
table.insert(list, object.country)
print(object.country)
end
return object
end
This code will print countries in Europe just once. When there was loop in there, it printed name of the country twice, because it did it for each element of object table (continent and country, hence two times).
Generic for loops in Programming in Lua (first edition).
I would also like to point out that list is quite useless at the moment. It is not being returned and stays local. On top of that, every time you call newcountry there is new list created. They are all unique - country objects are not added to single list. But again - I don't know what you are trying to accomplish.
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 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
Im new in matlab, Im trying to call a function inside a matlab GUI but I keep getting an error. Can you please help.
function PushMe_Callback(hObject, eventdata, handles)
set(handles.output_line,'String','I Got here');
Get_Length(Note_Vector,output,Counter,Total_num)
%------------------------------------------------------------
function Get_Length(Note_Vector,output,Counter,Total_num)
output = [ ];
while (1)
T = Total_num - Counter;
for j=1:T
[xml_input]=Get_Note(Note_Vector(j));
output = [output xml_input];
end
end
You have to get your data from the gui data. You can retrieve these data from the function "guidata".
In fact what happens, is that you define a variable in the "main function" but you cannot access this one.
What you should do is to add this variable in the handles in the "GUI_OpeningFcn" function:
Note_Vector = [ ];
output = [ ];
Counter = 0
for i=1:Total_num
Note_Vector = [Note_Vector Note+Shift];
end
handles.Note_Vector = Note_Vector;
handles.GLoutput = output; %handles.output is already the handle of your GUI, don't change it.
handles.counter=counter;
handles.Total_num=Total_num;
(...)
guidata(hObject, handles);
then you can either retrieve these data in PushMe_Callback by simply writing handles.Note_Vector OR you can retrieve them by doing the following in Get_Length function
handles = guidata(handle). In that case you'll have to put in input the handle of your GUI
Get_Length(Note_Vector,output,Counter,Total_num,handles.output)
I let you check the matlab help file concerning guidata() if you want more information.