Guide to Game Development/The Programming Language/VB.NET/Variables

Guide to Game Development/The Programming Language/VB.NET Variables Basic console input and outputs Basic math operators and Concatenation Different types of Variables This a table of all the different data types that a variable can be, you don't need to remember all of these, just a few. For now, just try and remember these: Integer Double Boolean Char String Whole Numbers The key thing here is to select the smallest one that you can run your program with to save resources, this is especially important with game development as a lot of RAM will be used. Byte 8-bits Unsigned byte: Can hold numbers in range: 0 to 255 (same as 0 to ) SByte 8-bits Signed byte: Can hold numbers in range: -128 to 127 (same as to ) Short 16-bits Signed short: Can hold numbers in range: -32,768 to 32,767 (same as to ) UShort 16-bits Unsigned short: Can hold numbers in range: 0 to 65,535 (same as 0 to ) Integer 32-bits Signed Integer: Can hold numbers in range: -2,147,483,648 to 2,147,483,647 (same as to ) UInteger 32-bits Unsigned Integer: Can hold numbers in range: 0 to 4,294,967,295 (same as 0 to ) Long 64-bits Signed Long: Can hold numbers in range: -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 (same as to ) ULong 64-bits Unsigned Integer: Can hold numbers in range: 0 to 18,446,744,073,709,551,615 (same as 0 to ) Decimal Numbers The key thing here is to select the smallest one that you can run your program with to save resources, this is especially important with game development as a lot of RAM will be used. Single 32-bits single-precision floating-point numbers ranging in value from -3.4028235E+38 through -1.401298E-45 for negative values and from 1.401298E-45 through 3.4028235E+38 for positive valueshttp://msdn.microsoft.com/en-us/library/xay7978z.aspx. Double 64-bits double-precision floating-point numbers that range in value from -1.79769313486231570E+308 through -4.94065645841246544E-324 for negative values and from 4.94065645841246544E-324 through 1.79769313486231570E+308 for positive valueshttp://msdn.microsoft.com/en-us/library/x99xtshc.aspx. Decimal 128-bits Holds signed 128-bit (16-byte) values representing 96-bit (12-byte) integer numbers scaled by a variable power of 10. The scaling factor specifies the number of digits to the right of the decimal point; it ranges from 0 through 28. With a scale of 0 (no decimal places), the largest possible value is +/-79,228,162,514,264,337,593,543,950,335 (+/-7.9228162514264337593543950335E+28). With 28 decimal places, the largest value is +/-7.9228162514264337593543950335, and the smallest nonzero value is +/-0.0000000000000000000000000001 (+/-1E-28)http://msdn.microsoft.com/en-us/library/xtba3z33.aspx. Text Char 16-bits Can hold one of 65536 Unicode character. String 16-bits per character Can hold many of the 65536 Unicode characters available in an order. Boolean Boolean 1-bit Holds a True/False state (0 or 1), one binary digit. Miscellaneous Date 64-bithttp://msdn.microsoft.com/en-us/library/3eaydw6e.aspx Can hold one date and time. Declaration of a variables You can create a variable with the following format: Dim NameOfVariable As DataTypeOfTheVariable Examples: Dim Num1 as Integer Dim Num2 as Double Dim Bool1 as Boolean Dim Char1 as Char Dim Str1 as String If you want to make many variables of the same data type it can be done like so: Dim NameOfVariable,NameOfVariable2,NameOfVariable3,... As DataTypeOfTheVariables Example: Dim Num1, Num2, Num3 as Integer Setting the value for a variable There are two way which you can set the state of a variable: On the declaration line Standalone statement Standalone statement mixed with math (will be shown at a later date). Example of setting value on a declaration line: Dim Num1 as Integer = 5 Example of setting value as a standalone statement: Num1 = 5 Example: This code: Dim Num1 as integer = 10 Console.WriteLine(Num1) Num1 = -4 Console.WriteLine(Num1) 'Stopping the console from closing Console.ReadLine() Will output: 10 -4 Naming conventions When naming variables, you should name them using lower camel casehttp://c2.com/cgi/wiki?LowerCamelCase thisIsWhereYouWriteVariablesLikeThis itIsLowerBecauseTheFirstLetterIsLowerCase References 100%