how to create qr code using vb.net Dim intMyInteger As Integer in VS .NET

Printer Code-128 in VS .NET Dim intMyInteger As Integer

To declare a variable named intMyInteger as an integer, enter the following:

Understanding Visual Basic Fundamentals To declare a variable named dbMyDatabase as a database object, enter the following:

To declare an array named strMyString that contains fixed-length strings that are 20 characters long and contains 50 entries from 51 through 100, enter the following:

Dim strMyString(51 To 100) As String * 20

Public Sub NewTableExample() Dim db As DAO.Database Dim tdf As New DAO.TableDef, _ fld1 As New DAO.Field, _ fld2 As New DAO.Field Initialize the table name tdf.Name = MyTable Set the name of the first field fld1.Name = MyField1 ' Set its data type fld1.Type = dbLong ' Append the first field to the Fields ' collection of the table tdf.Fields.Append fld1 ' Set up the second field fld2.Name = "MyField2" fld2.Type = dbText fld2.Size = 20 ' Append the second field to the table tdf.Fields.Append fld2 ' Establish an object on the current database Set db = CurrentDb ' Create a new table by appending tdf to ' the Tabledefs collection of the database db.TableDefs.Append tdf End Sub

See Collections, Objects, Properties, and Methods on page 791 for details about working with DAO objects. See Functions and Subroutines on page 812 for details about the Sub statement.

To declare an object variable to respond to events in another class module, enter the following:

Option Explicit Dim WithEvents objOtherClass As MyClass Sub LoadClass () Set objOtherClass = New MyClass End Sub

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To declare a database variable, a new table variable, and two new field variables for the table; set up the objects; and append the new table to the Tabledefs collection, enter the following:

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Sub objOtherClass_Signal(ByVal strMsg As string) MsgBox "MyClass Signal event sent this " & _ "message: " & strMsg End Sub

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In class module MyClass, code the following:

Option Explicit Public Event Signal(ByVal strMsg As String) Public Sub RaiseSignal(ByVal strText As String) RaiseEvent Signal(strText) End Sub

In any other module, execute the following statement:

MyClass.RaiseSignal "Hello"

Use an Enum statement in a module Declarations section to assign long integer values to named members of an enumeration. You can use an enumeration name as a restricted Long data type.

Enumerations are constant values that you cannot change when your code is running. Include the Public keyword to define an enumeration that is available to all procedures in all modules in your database. Include the Private keyword to declare an enumeration that is available only within the module where the declaration is made. Enumerations are public by default. You must declare at least one member within an enumeration. If you do not provide a <long integer expression> assignment, Visual Basic adds 1 to the previous value or assigns 0 if the member is the first member of the enumeration. The <long integer expression> cannot include variables, user-defined functions, or Visual Basic built-in functions (such as CLng). You can include simple literals and other previously defined constants or enumerations. Enumerations are most useful as a replacement for the Long data type in a Function or Sub statement. When you call the function or sub procedure in code, you can use one of the enumeration names in place of a variable, constant, or literal. If you select the Auto List Members option (see Figure 22-3), Visual Basic displays the available names in a drop-down list as you type the sub or function call in your code.

To declare a public enumeration for days of the week and use the enumeration in a procedure, enter the following:

Option Explicit Public Enum DaysOfWeek Sunday = 1 Monday Tuesday Wednesday Thursday Friday Saturday End Enum Public Function NextDate(lngDay As DaysOfWeek) As Date ' This function returns the next date ' that matches the day of week requested Dim intThisDay As Integer, datDate As Date ' Get today datDate = Date ' Figure out today's day of week intThisDay = WeekDay(datDate) ' Calculate next day depending on ' whether date requested is higher or lower If intThisDay < lngDay Then NextDate = datDate + (lngDay intThisDay) Else NextDate = datDate + (lngDay + 7) intThisDay End If End Function

You can test the function from the Immediate window by entering the following:

NextDate(Monday)

Use the Event statement in the Declarations section of a class module to declare an event that can be raised within the module. In another module, you can define an object variable using the WithEvents keyword, set the variable to an instance of this class module, and then code procedures that respond to the events declared and triggered within this class module.