Visual Basic .net

Files

Reading text files line by line:
Dim f1 As Long
dim filestring as string

f1 = FreeFile()
FileOpen(f1, My.Application.Info.DirectoryPath & "\filename.txt", OpenMode.Input)
Do Until EOF(f1)


filestring=LineInput(f1)

Loop
FileClose(f1)
Note: My.Application.Info.DirectoryPath & "\filename.txt" may be replaced by "C:\some_path\file.txt"

Writing text files line by line:
Dim f1 As Long


f1 = FreeFile()
FileOpen(f1, My.Application.Info.DirectoryPath & "\filename.txt", OpenMode.Output
Print(f1, "This is line 1")
Print(f1, "This is line 2")
FileClose(f1)


Datatypes

Visual Basic type	.NET Runtime type	structure Storage size	Value range
Boolean	System.Boolean	4 bytes	True or False
Byte	System.Byte	1 byte	0 to 255 (unsigned)
Char	System.Char	2 bytes	0 to 65535 (unsigned)
Date	System.DateTime	8 bytes	January 1, 1 CE to December 31, 9999
Decimal	System.Decimal	12 bytes	+/-79,228,162,514,264,337,593,543,950,335 with no decimal point; +/-7.9228162514264337593543950335 with 28 places to the right of the decimal; smallest non-zero number is +/-0.0000000000000000000000000001
Double	System.Double	8 bytes	-1.79769313486231E308 to -4.94065645841247E-324 for negative values; 4.94065645841247E-324 to 1.79769313486232E308 for positive values
Integer	System.Int32	4 bytes	-2,147,483,648 to 2,147,483,647
Long	System.Int64	8 bytes	-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
Object	System.Object (class)	4 bytes	Any type can be stored in a variable of type Object
Short	System.Int16	2 bytes	-32,768 to 32,767
Single	System.Single	4 bytes	-3.402823E38 to -1.401298E-45 for negative values; 1.401298E-45 to 3.402823E38 for positive values
String	System.String (class)	10 bytes + (2 * string length)	0 to approximately two billion Unicode characters
User-Defined Type (structure)	(inherits from System.ValueType)	Sum of the sizes of its members	Each member of the structure has a range determined by its data type and independent of the ranges of the other members