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Format Function 

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Returns a string formatted according to instructions contained in a format String expression.

Public Shared Function Format( _
   ByVal Expression As Object, _
   Optional ByVal Style As String = "" _
) As String

Parameters

  • Expression
    Required. Any valid expression.
  • Style
    Optional. A valid named or user-defined format String expression.

Settings

For information on how to create the Style argument, see the appropriate topic listed below:

To format Do this

Numbers

Use predefined numeric formats or create user-defined numeric formats.

Dates and times

Use predefined date/time formats or create user-defined date/time formats.

Date and time serial numbers

Use date and time formats or numeric formats.

If you try to format a number without specifying Style, the Format function provides functionality similar to the Str function, although it is internationally aware. However, positive numbers formatted as strings using the Format function don't include a leading space reserved for the sign of the value; those converted using the Str function retain the leading space.

Remarks

If you are formatting a nonlocalized numeric string, you should use a user-defined numeric format to ensure that you get the look you want.

The System.String.Format method also provides similar functionality.

Example

This example shows various uses of the Format function to format values using both String formats and user-defined formats. For the date separator (/), time separator (:), and the AM/PM indicators (t and tt), the actual formatted output displayed by your system depends on the locale settings the code is using. When times and dates are displayed in the development environment, the short time format and short date format of the code locale are used.

Note

For locales that use a 24-hour clock, the AM/PM indicators (t and tt) display nothing.

Dim TestDateTime As Date = #1/27/2001 5:04:23 PM#
Dim TestStr As String
' Returns current system time in the system-defined long time format.
TestStr = Format(Now(), "Long Time")
' Returns current system date in the system-defined long date format.
TestStr = Format(Now(), "Long Date")
' Also returns current system date in the system-defined long date 
' format, using the single letter code for the format.
TestStr = Format(Now(), "D")

' Returns the value of TestDateTime in user-defined date/time formats.
' Returns "5:4:23".
TestStr = Format(TestDateTime, "h:m:s")
' Returns "05:04:23 PM".
TestStr = Format(TestDateTime, "hh:mm:ss tt")
' Returns "Saturday, Jan 27 2001".
TestStr = Format(TestDateTime, "dddd, MMM d yyyy")
' Returns "17:04:23".
TestStr = Format(TestDateTime, "HH:mm:ss")
' Returns "23".
TestStr = Format(23)

' User-defined numeric formats.
' Returns "5,459.40".
TestStr = Format(5459.4, "##,##0.00")
' Returns "334.90".
TestStr = Format(334.9, "###0.00")
' Returns "500.00%".
TestStr = Format(5, "0.00%")

Requirements

Namespace: Microsoft.VisualBasic

Module: Strings

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

See Also

Reference

String Manipulation Summary
Different Formats for Different Numeric Values (Format Function)
Predefined Date/Time Formats (Format Function)
Predefined Numeric Formats (Format Function)
Str Function
Type Conversion Functions
User-Defined Date/Time Formats (Format Function)
User-Defined Numeric Formats (Format Function)
Format