auto generate barcode vb net Copyright 2001 by McGraw-Hill, Inc. Click Here for Terms of Use. in Visual Studio .NET

Generating QR in Visual Studio .NET Copyright 2001 by McGraw-Hill, Inc. Click Here for Terms of Use.

Copyright 2001 by McGraw-Hill, Inc. Click Here for Terms of Use.
Scanning QR In .NET Framework
Using Barcode Control SDK for Visual Studio .NET Control to generate, create, read, scan barcode image in .NET applications.
QR Creation In Visual Studio .NET
Using Barcode creation for Visual Studio .NET Control to generate, create QR-Code image in .NET applications.
CHAP. 2]
Recognizing QR Code ISO/IEC18004 In VS .NET
Using Barcode scanner for VS .NET Control to read, scan read, scan image in VS .NET applications.
Print Barcode In VS .NET
Using Barcode printer for .NET framework Control to generate, create barcode image in Visual Studio .NET applications.
VISUAL BASIC FUNDAMENTALS
Reading Barcode In VS .NET
Using Barcode scanner for .NET framework Control to read, scan read, scan image in .NET framework applications.
QR Code Encoder In Visual C#
Using Barcode maker for .NET Control to generate, create QR Code image in VS .NET applications.
EXAMPLE 2.1
Quick Response Code Maker In .NET Framework
Using Barcode creator for ASP.NET Control to generate, create QR Code 2d barcode image in ASP.NET applications.
Generating QR Code ISO/IEC18004 In Visual Basic .NET
Using Barcode generator for Visual Studio .NET Control to generate, create Quick Response Code image in .NET applications.
Several Visual Basic numeric constants are shown below. Note that each quantity (each row) can be written in several different ways.
EAN / UCC - 13 Maker In Visual Studio .NET
Using Barcode generator for .NET Control to generate, create UCC - 12 image in Visual Studio .NET applications.
GS1 DataBar Limited Creation In .NET
Using Barcode generator for Visual Studio .NET Control to generate, create GS1 DataBar image in .NET applications.
0 1 5280 1492 .0000613 3000000 +0 +1 5.28E+3 0.1492D+4 6.13E 5 3D6 0 0.1E+1 .528E4 1.492D+3 613E 7 3D+6 10E 1 52.8E2 +14.92D2 0.613E 4 0.3D7
Encode Barcode In VS .NET
Using Barcode creator for .NET framework Control to generate, create bar code image in Visual Studio .NET applications.
EAN - 14 Maker In VS .NET
Using Barcode encoder for VS .NET Control to generate, create UPC Shipping Container Symbol ITF-14 image in VS .NET applications.
2.2 STRING CONSTANTS A string constant is a sequence of characters (i.e., letters, numbers and certain special characters, such as +, , /, *, =, $, ., etc.), enclosed in quotation marks. Blank spaces can be included within a string. A quotation mark can also be placed within a string, but it must be written as two adjacent quotation marks (see the last line in the example below). String constants are used to represent nonnumeric information, such as names, addresses, etc. There is no practical restriction on the maximum number of characters that can be included within a string constant. Thus, the maximum length of a string constant can be considered infinite.
EAN-13 Maker In Java
Using Barcode printer for BIRT Control to generate, create EAN 13 image in BIRT applications.
Make DataBar In Java
Using Barcode maker for Java Control to generate, create GS1 DataBar Stacked image in Java applications.
EXAMPLE 2.2
Generating GS1 - 13 In None
Using Barcode encoder for Online Control to generate, create European Article Number 13 image in Online applications.
Bar Code Drawer In C#.NET
Using Barcode generation for Visual Studio .NET Control to generate, create bar code image in Visual Studio .NET applications.
Several string constants are shown below.
Draw Code 3 Of 9 In Java
Using Barcode creator for Java Control to generate, create Code 39 Extended image in Java applications.
Barcode Scanner In C#.NET
Using Barcode reader for .NET framework Control to read, scan read, scan image in Visual Studio .NET applications.
"SANTA CLAUS" "$19.95" "X1 = " "The answer is " "Please type a value for C:" "Welcome to the 21st Century" "3730425" "Do you wish to try again "
Create UPC - 13 In Java
Using Barcode maker for Java Control to generate, create EAN-13 image in Java applications.
Scanning Code 128A In None
Using Barcode decoder for Software Control to read, scan read, scan image in Software applications.
"The professor said, ""Please don't snore in class"" "
2.3 VARIABLES A variable is a name that represents a numerical quantity, a string, or some other basic data item (e.g., a date, true/false condition, etc.). The following rules apply to the naming of variables: 1. A variable name must begin with a letter. Additional characters may be letters or digits. Certain other characters may also be included, though the period and special data-typing characters (e.g., %, &, !, #, and $) are not permitted. In general, it is good programming practice to avoid the use of characters other than letters and digits. A variable name cannot exceed 255 characters. As a practical matter, however, variable names rarely approach this size. Visual Basic does not distinguish between uppercase and lowercase letters. Many programmers use uppercase letters as word separators within a single variable name (e.g., FreezingPoint, TaxRate, etc.) Visual Basic includes a number of reserved words (e.g., Dim, If, Else, Select, Case, Do, etc.). These reserved words represent commands, function names, etc. They cannot be used as variable names.
2. 3. 4.
VISUAL BASIC FUNDAMENTALS
[CHAP. 2
EXAMPLE 2.3
Several variable names are shown below.
Area Counter Radius CustomerName X xmax Account_Number C3 UnpaidBalance
2.4 DATA TYPES AND DATA DECLARATIONS Visual Basic supports all common data types, including Integer, Long (i.e., long integer), Single, Double and String. The language also supports other data types, such as Boolean, Byte, Currency and Date data, as well as Variant-type data (see below) and user-defined data types. The Dim statement is used to associate variables with specific data types. This process, which is common to all modern programming languages, is known as data declaration, or simply declaration. In general terms, the Dim statement is written as
Dim variable name 1 As data type 1, variable name 2 As data type 2, etc.
EXAMPLE 2.4
Several variable declarations are shown below.
Dim Counter As Integer Dim Area As Single Dim StudentName As String Dim StudentName As String * 30 Dim TaxRate As Single, Income As Double, Taxes As Double, Dependents As Integer
The first line declares Counter to be an integer-type variable, and the second line declares that Area is a singleprecision real variable. The third line declares StudentName to be a string variable of unspecified length; in the fourth line, however, StudentName is declared to be a string variable of fixed length, not exceeding 30 characters. Finally, the last line declares TaxRate to be a single-precision real variable, Income and Taxes as double-precision real variables, and Dependents as an integer variable.
Variants Visual Basic allows variables to be undeclared if the programmer so chooses. In such cases, the data type of the variable is determined implicitly by the value that is assigned to the variable. Such variables are referred to as Variant-type variables, or simply as variants. On the surface, the use of variants appears to simplify the program development process. This is a false perception, however, as the use of variants is computationally inefficient, and it compromises the clarity of a program. Good programming practice suggests that the use of variants be avoided. Use explicitly declared variables instead.
Named Constants It is also possible to define named constants in Visual Basic. Named constants are similar to variables. However, variables can be reassigned different values within a program, whereas named constants remain unchanged throughout a program.
CHAP. 2]
Copyright © OnBarcode.com . All rights reserved.