Visual basic data types pdf full#
If you do not need the full range of the Double data type, you can use the Single data type, which can hold floating-point numbers from -3.4028235E+38 through 3.4028235E+38. Small Magnitudesįor numbers with the smallest possible magnitude (closest to 0), Double variables can hold numbers as small as -4.94065645841246544E-324 for negative values and 4.94065645841246544E-324 for positive values. However, operations with Double are not as fast as with the integral types such as Integer. Performanceĭouble is the most efficient of the fractional data types, because the processors on current platforms perform floating-point operations in double precision. Nonintegral number values can be expressed as mmmEeee, in which mmm is the mantissa (the significant digits) and eee is the exponent (a power of 10). Floating-point types support fewer significant digits than Decimal but can represent values of greater magnitude.
The Decimal data type retains complete accuracy to 28 decimal places.įloating-point ( Single and Double) numbers have larger ranges than Decimal numbers but can be subject to rounding errors. The Double data type is faster and requires less memory, but it is subject to rounding errors. The advantage is the precision of the values. You can use Decimal variables for money values. Decimal numbers have a binary integer value and an integer scaling factor that specifies what portion of the value is a decimal fraction. If a variable can contain a fraction, declare it as one of these types.ĭecimal is not a floating-point data type. The nonintegral numeric data types are Decimal (128-bit fixed point), Single Data Type (32-bit floating point), and Double Data Type (64-bit floating point). Nonintegral data types are those that represent numbers with both integer and fractional parts. In particular, UInteger shares with Integer the distinction of being the most efficient of all the elementary numeric data types. In terms of performance, each unsigned type is exactly as efficient as its corresponding signed type. Each of these data types can hold a positive integer twice as large as its corresponding signed type ( SByte, Short, Integer, and Long). If you know that your variable never needs to hold a negative number, you can use the unsigned types Byte, UShort, UInteger, and ULong. However, operations with Short and SByte are somewhat slower than with Integer. If you have a very large number of variables that hold small integers, the common language runtime can sometimes store your Short and SByte variables more efficiently and save memory consumption. For the smallest integer range, the SByte data type holds integers from -128 through 127. If you do not need the full range of the Integer data type, you can use the Short data type, which can hold integers from -32,768 through 32,767. However, operations with Decimal numbers are considerably slower than with any other numeric data type. If you need even larger values, you can use the Decimal Data Type.
Operations with Long are slightly slower than with Integer. If you need to hold an integer larger than the Integer data type can hold, you can use the Long data type instead. They are fastest with the Integer and UInteger types in Visual Basic. PerformanceĪrithmetic operations are faster with integral types than with other data types. If a variable contains binary data, or data of unknown nature, declare it as one of these types. The unsigned integral types are Byte Data Type (8-bit), UShort Data Type (16-bit), UInteger Data Type (32-bit), and ULong Data Type (64-bit). If a variable always stores integers rather than fractional numbers, declare it as one of these types. The signed integral data types are SByte Data Type (8-bit), Short Data Type (16-bit), Integer Data Type (32-bit), and Long Data Type (64-bit). Integral data types are those that represent only numbers without fractional parts. Integral types represent only whole numbers (positive, negative, and zero), and nonintegral types represent numbers with both integer and fractional parts.įor a table showing a side-by-side comparison of the Visual Basic data types, see Data Types. Visual Basic supplies several numeric data types for handling numbers in various representations.
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