Enumerating Properties of Controls
I've been playing with Typelib Information (TBLINF32.DLL) to enumerate the Properties of all the Controls on a Form and determine whether specific ones are Read only.
Basic code is
Code:
Dim TypeLib As TLI.InterfaceInfo
Dim Prop As TLI.MemberInfo
Debug.Print pObject.Name
Set TypeLib = TLI.InterfaceInfoFromObject(pObject)
For Each Prop In TypeLib.Members
Debug.Print , Prop.Name & " " & Prop.InvokeKind
Next
where pObject is the Control in question
The output from a ComboBox looks something like this
Code:
Combo1
_DEFAULT 2
_DEFAULT 4
NAME 2
STYLE 2
INDEX 2
BACKCOLOR 2
BACKCOLOR 4
FORECOLOR 2
FORECOLOR 4
LEFT 2
LEFT 4
TOP 2
TOP 4
WIDTH 2
WIDTH 4
HEIGHT 2
HEIGHT 4
ENABLED 2
ENABLED 4
VISIBLE 2
VISIBLE 4
MOUSEPOINTER 2
MOUSEPOINTER 4
TEXT 2
TEXT 4
FONTNAME 2
FONTNAME 4
FONTBOLD 2
FONTBOLD 4
FONTITALIC 2
FONTITALIC 4
FONTSTRIKETHRU 2
FONTSTRIKETHRU 4
FONTUNDERLINE 2
FONTUNDERLINE 4
FONTSIZE 2
FONTSIZE 4
TABINDEX 2
TABINDEX 4
LISTCOUNT 2
LISTINDEX 2
LISTINDEX 4
LIST 2
LIST 4
SORTED 2
SELSTART 2
SELSTART 4
SELLENGTH 2
SELLENGTH 4
SELTEXT 2
SELTEXT 4
PARENT 2
DRAGMODE 2
DRAGMODE 4
DRAGICON 2
DRAGICON 4
DRAGICON 8
TABSTOP 2
TABSTOP 4
TAG 2
TAG 4
HWND 2
ITEMDATA 2
ITEMDATA 4
NEWINDEX 2
HELPCONTEXTID 2
HELPCONTEXTID 4
MOUSEICON 2
MOUSEICON 4
MOUSEICON 8
FONT 2
FONT 8
DATAFIELD 2
DATAFIELD 4
DATACHANGED 2
DATACHANGED 4
WHATSTHISHELPID 2
WHATSTHISHELPID 4
APPEARANCE 2
APPEARANCE 4
CONTAINER 2
CONTAINER 8
INTEGRALHEIGHT 2
RIGHTTOLEFT 2
RIGHTTOLEFT 4
TOOLTIPTEXT 2
TOOLTIPTEXT 4
OLEDRAGMODE 2
OLEDRAGMODE 4
OLEDROPMODE 2
OLEDROPMODE 4
LOCKED 2
LOCKED 4
TOPINDEX 2
TOPINDEX 4
CAUSESVALIDATION 2
CAUSESVALIDATION 4
DATAMEMBER 2
DATAMEMBER 4
DATAFORMAT 2
DATAFORMAT 8
DATASOURCE 2
DATASOURCE 8
CLEAR 1
ADDITEM 1
REMOVEITEM 1
SETFOCUS 1
REFRESH 1
ZORDER 1
DRAG 1
MOVE 1
SHOWWHATSTHIS 1
OLEDRAG 1
From what I curently understand, a Prop.InvokeKind of 2 (INVOKE_PROPERTYGET) means it's a Readable property and a Prop.InvokeKind of 4 (INVOKE_PROPERTYPUT) means it's Writeable.
The issue is that, for example, the 'Height' property of a ComboBox is read only, yet the results above suggest it's Read/ Write. If you note, the ListIndex Property does not have a Prop.InvokeKind of INVOKE_PROPERTYPUT which is what I would expect.
Am I missing something or is there a 'better' way to achieve the objective? (apart from attempting to assign a value to the Property and using in-line Error Handling to trap errors)
BTW The overall objective is to attempt to build a 'generic' Form Resize Class / Module (yes,I know it's been done a thousand times before, but I've never done it- this is an exercise for me rather than anything 'useful') and in order to do so it's required to be able to identify whether a particular Property exists (e.g.Height) and whether it's writable.
Re: Enumerating Properties of Controls
The InvokeKind enumeration is only responsible for how the function is to be invoked, according to this :
http://msdn.microsoft.com/en-us/library/aa911289.aspx
INVOKE_FUNC
Indicates that the member is called using standard function invocation syntax.
INVOKE_PROPERTYGET
Indicates that the function is invoked using standard property-access syntax.
INVOKE_PROPERTYPUT
Indicates that the function is invoked using property value assignment syntax. Syntactically, a typical programming language might represent changing a property in the same way as assignment, for example, object.property : = value
INVOKE_PROPERTYPUTREF
Indicates that the function is invoked using property reference assignment syntax.
So, it seems as if you're understanding it a bit wrong :)
This may also be helpful :
http://www.xtremevbtalk.com/showthread.php?t=78324
It just takes your code a step further.
Re: Enumerating Properties of Controls
Quote:
Originally Posted by
Doogle
I've been playing with Typelib Information (TBLINF32.DLL) to enumerate the Properties of all the Controls on a Form and determine whether specific ones are Read only.
From what I curently understand, a Prop.InvokeKind of 2 (INVOKE_PROPERTYGET) means it's a Readable property and a Prop.InvokeKind of 4 (INVOKE_PROPERTYPUT) means it's Writeable.
The issue is that, for example, the 'Height' property of a ComboBox is read only, yet the results above suggest it's Read/ Write. If you note, the ListIndex Property does not have a Prop.InvokeKind of INVOKE_PROPERTYPUT which is what I would expect.
Am I missing something or is there a 'better' way to achieve the objective? (apart from attempting to assign a value to the Property and using in-line Error Handling to trap errors)
BTW The overall objective is to attempt to build a 'generic' Form Resize Class / Module (yes,I know it's been done a thousand times before, but I've never done it- this is an exercise for me rather than anything 'useful') and in order to do so it's required to be able to identify whether a particular Property exists (e.g.Height) and whether it's writable.
How do you figure, that Height would be read-only for a combobox? Or that you would expect that ListIndex is read-only, since in your example above i can clearly see a LISTINDEX 4, which suggests writable. Or did you mean ListCount?
I've been setting Height and ListIndex for a ComboBox during Runtime since Adam & Eve...
Re: Enumerating Properties of Controls
Quote:
Originally Posted by
Zvoni
I've been setting Height and ListIndex for a ComboBox during Runtime since Adam & Eve...
I meant ListCount.
I get a Run-time error if I try to set a ComboBox Height property at run time. Error 383 'Height' property is read only
Perhaps the Serpent in the Garden of Eden is playing around again :)
Re: Enumerating Properties of Controls
I just did a test with a ComboBox, but in Excel (since i don't have the VB-IDE at work).
No difference by setting different Styles (Combo vs. DropDown, Plain vs. Options etc.)
I could change the height at runtime.
Maybe you have set some weird property which needs a read-only-height.:confused:
EDIT: I think my problem is, that in Excel-VBA you can change the height at Runtime
I've found something on codeguru: http://forums.codeguru.com/showthrea...omboBox-Height
Re: Enumerating Properties of Controls
Quote:
Originally Posted by
Zvoni
I just did a test with a ComboBox, but in Excel
You'll note that we are in the VB 6 Froum as opposed to VBA or Office.
I can assure you that no 'wierd property' has been set. Try it with VB6 when you have a chance :)
Code:
Private Sub Form_Load()
Combo1.Height = 3000
End Sub
Re: Enumerating Properties of Controls
You're right. After some research i found out, that in VB6 it's really read-only.
It seems the only "official" way to change the height of a ComboBox is to change its Font-Size, if you don't want to use the hack with the MoveWindow-API
Since changing a combobox's Fontsize also changes its height, you could argue, that Height as such has to be "writable" hence the INVOKE_PROPERTYPUT even if you cannot access it directly.
At least that's my conclusion
Re: Enumerating Properties of Controls
Yes, I think I've concluded that there's a PROPERTYPUT for the Height Property because it can be set at Design-time and it's at run-time that the error occurrs. If I try to set a value for ListCount I get a compile error. It begs the question: "How does VB run-time work out that the Property is Read Only?" - more Googling I suppose.
Re: Enumerating Properties of Controls
The funny thing is, if you set a combobox to "simple combo" (like a textbox) you can change its height at run time.
at least that is what i could find
Re: Enumerating Properties of Controls
Quote:
Originally Posted by
Doogle
*snip* It begs the question: "How does VB run-time work out that the Property is Read Only?" - more Googling I suppose.
http://msdn.microsoft.com/en-us/libr...=vs.60%29.aspx
It's not the vb-runtime, it's the design of the control!
