X as variant and y as integer.
Variant variable size = 22 + Actual data type size.
Instr – integer (Numeric position)
Strcmp - integer ( if both the string are equal they result = 0)
Strcmp (Str1, Str2, Comparetype)
Comparing mode = 0 – Binary Comparing
1 – Textual Comparing
Frm, bas, cls, res, vbx, ocx, frx, vbp, exe
When some controls like grid and third party control placed in our application then it will create frx in run time.
Dateadd(), Datediff(), Datepart(), Cdate()
15/4 = 3.75 and 15\4 = 3
ISOperator – Returns Boolean.
2. function and sub procedures (Ask what is the diff. Between them?)
In the general declarations section. To trap undeclared variables.
Scope sharable between projects.
Assigning variable with defined memory space.
Late Binding - Memory size is allotted in later stage.
Ex:- Dim x as object
Early Binding - Memory size is allotted while declaring itself.
New Key word is important.
Ex:- Dim x as New Object
Let – Value is assigned to ActiveX Object from the form.
Let – Value is retried to ActiveX Object from the form.
Control. Restricted data input as well as formatted data output.
State 0 – Source control is being dragged with the range of a target.
1 – Out of the range of a target.
2 – One positon in the target to another.
For each currentcontrol in controls
if typeof currentcontrol is TextBox then
Group of control share the same name. Max 32, 767.
VbModaless – 0 (Zero) – We can able to place another window above this form.
Invalid procedure call or argument (Run time error – 5)
Std Global with in the project. Cls Global through out the all project only thing is we want to set the type lib. Class Modules can be Instantiated.
Private – Only for the Specific Module.
Public not creatable – Private & Public
Multi Use - Variable we have to declare.
Single Use – Not possible through dll.
Global Multiuse – Have variable not Required to Declare.
Global Single Use - " Only for exe.
Declare function "
We can have only one MDI form for a project. Multiple Document Interface. This form type is VBModal. We have set the Child property of the forms to True to place forms inside this MDI.
Style availables 1. VbCascade 2. VbTitle Horizontal
Inprocess – It will run with in the memory. ( Local Machine).
Out of Process – It will run out of the memory Normally in the server side.
LOB (Large Object Data type).
CLOB (Stores Character Objects).
BLOB ( Store Binary Objects such as Graphic, Video Chips and Sound files).
BFILE(Store file pointers to LOB It may Contain filename for photo’s store on CD_ROM).
Object.Zorder = 1 or 0 Place a Specified mdiform form or control at the font or back of the z-order with n its Graphical Level.
Create Object Ex:-Ole-Automation . No need refer the object library.
Binding Procedure Early and Late Binding ( Can be Remove from the Memory).
No Properties Available. Only the methods they are SetText, GetText, Setdata(), Getformat(), Clear.
Libraries of procedures external to the application but can be called from the application.
It is tab control to place our controls with in the form in multiple sheets.
Index starts with 1. And to identify
If Tabstrip1.SelectedItem.Index = 1 Then
To list the hierarchial list of the node objects. Such of files and Directories.
Enables an application to exposes objects and methods to other Applications.
No need to reserve memory. No need to write functions. Object library that simplify programming tasks. i.e., No need to Object library. (OLB, TLB).
Create Object - To create an instance of an object.
Get Object – To get the reference to an existing object.
Properties – Public variable of a Class
Method – Public procedure of a class
Similarly to arrays but is preferred over an array because of the following reasons.
1. A collection objects uses less Memory than an array.
2. It provides methods to add and delete members.
3. It does not required reason statement when objects are added or deleted.
4. It does not have boundary limitations.
Its Scope will be available through out the life time.
Private cannot be used in front of DIM.
Instance of specific copy of a class with its own settings for the properties defined in that class.
Note: The implicity defined variable is never equal to nothing.
Public , private, Friend
This cannot have user interface. This can be used for the COM creation.
Simple, Dropdown list – We can type and select.
Dropdown Compo – Only Drop Down.
Simple –Single Select , Extended. – Multiple Select.
Predefined, Custom, User Defined.
It is difficult to use database objects declared in a module from within a form.
Screen.MousePointer = VBHourGlass/VBNormal.
If(Msgbox("Do you want to delete this Record",VbYesNo)=VbYes)Then End if