Format

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Description The Format function provides 'C' like formatting of multiple of simple data types into a string. It provides very precise control over this formatting.    The Formatting parameter defines how the Data array is manipulated into the returned string.    The Formatting string can comprise a mix of ordinary characters (that are passed unchanged to the result string), and data formatting characters. This formatting is best explained by the example code.    In simple terms, each data formatting substring starts with a % and ends with a data type indicator :    d  = Decimal (integer) e  = Scientific f  = Fixed g  = General m  = Money n  = Number (floating) p  = Pointer s  = String u  = Unsigned decimal x  = Hexadecimal   The general format of each formatting substring is as follows:    %[Index:][-][Width][.Precision]Type    where the square brackets refer to optional parameters, and the : . - characters are literals, the first 2 of which are used to identify two of the optional arguments.    Version 2 of this function is for use within threads. You furnish the FormatSettings record before invoking the call. It takes a local copy of global formatting variables that make the routine thread safe.   Notes Various formatting options, such as DecimalSeparatorand CurrencyString are used for some of these formatting options. See the more specific versions of data display commands, such as CurrToStrF for details. Conference call services can be available to discuss these formatting options.   Related commands CurrencyDecimals   Defines decimal digit count in the Format function CurrencyFormat   Defines currency string placement in curr display functions CurrencyString   The currency string used in currency display functions CurrToStrF   Convert a currency value to a string with formatting DecimalSeparator   The character used to display the decimal point FloatToStrF   Convert a floating point value to a string with formatting FormatCurr   Rich formatting of a currency value into a string FormatDateTime   Rich formatting of a TDateTime variable into a string FormatFloat   Rich formatting of a floating point number into a string NegCurrFormat   Defines negative amount formatting in currency displays ThousandSeparator   The character used to display the thousands separator  Download this web site as a Windows program.

Example code : Showing all of the formatting data types var   text : string; begin   // Just 1 data item   ShowMessage(Format('%s', ['Hello']));   // A mix of literal text and a data item   ShowMessage(Format('String = %s', ['Hello']));   ShowMessage('');   // Examples of each of the data types   ShowMessage(Format('Decimal          = %d', [-123]));   ShowMessage(Format('Exponent         = %e', [12345.678]));   ShowMessage(Format('Fixed            = %f', [12345.678]));   ShowMessage(Format('General          = %g', [12345.678]));   ShowMessage(Format('Number           = %n', [12345.678]));   ShowMessage(Format('Money            = %m', [12345.678]));   ShowMessage(Format('Pointer          = %p', [addr(text)]));   ShowMessage(Format('String           = %s', ['Hello']));   ShowMessage(Format('Unsigned decimal = %u', [123]));   ShowMessage(Format('Hexadecimal      = %x', [140])); end; Show full unit code    Hello    String = Hello        Decimal          = -123    Exponent         = 1.23456780000000E+004    Fixed            = 12345.68    General          = 12345.678    Number           = 12,345,68    Money            = ?12,345.68    Pointer          = 0069FC90    String           = Hello    Unsigned decimal = 123    Hexadecimal      = 8C     Example code : Using the index, width and precision values begin   // The width value dictates the output size   // with blank padding to the left   // Note the <> characters are added to show formatting   ShowMessage(Format('Padded decimal    = <%7d>', [1234]));   // With the '-' operator, the data is left justified   ShowMessage(Format('Justified decimal = <%-7d>', [1234]));   // The precision value forces 0 padding to the desired size   ShowMessage(Format('0 padded decimal  = <%.6d>', [1234]));   // A combination of width and precision   // Note that width value precedes the precision value   ShowMessage(Format('Width + precision = <%8.6d>', [1234]));   // The index value allows the next value in the data array   // to be changed   ShowMessage(Format('Reposition after 3 strings = %s %s %s %1:s %s',                      ['Zero', 'One', 'Two', 'Three']));   // One or more of the values may be provided by the   // data array itself. Note that testing has shown that an *   // for the width parameter can yield EConvertError.   ShowMessage(Format('In line           = <%10.4d>', [1234]));   ShowMessage(Format('Part data driven  = <%*.4d>', [10, 1234]));   ShowMessage(Format('Data driven       = <%*.*d>', [10, 4, 1234])); end; Show full unit code    Padded decimal    = <   1234>    Justified decimal = <1234   >    0 padded decimal  = <001234>    Width + precision = <  001234>    Reposition after 3 strings = Zero One Two One Two    In line           = <      1234>    Part data driven  = <      1234>    Data driven       = <      1234>