DelphiBasics
ShowMessageFmt
Procedure		 Display formatted data in a simple dialog with an OK button Dialogs unit
 procedure ShowMessageFmt(const Formatting string; const Data array of const);
Description
The ShowMessageFmt procedure provides 'C' like formatting of multiple of simple data types into a string that is displayed in a single. It provides very precise control over this formatting.
 
The Formatting parameter defines how the Data array is manipulated into the displayed string.
 
The dialog has an OK button to allow the user to register the message and close the dialog.
 
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.
Related commands
InputBoxDisplay a dialog that asks for user text input, with default
InputQueryDisplay a dialog that asks for user text input
MessageDlgDisplays a message, symbol, and selectable buttons
MessageDlgPosDisplays a message plus buttons at a given screen position
PromptForFileNameShows a dialog allowing the user to select a file
ShowMessageDisplay a string in a simple dialog with an OK button
ShowMessagePosDisplay a string in a simple dialog at a given screen position
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Example code : Showing all of the formatting data types
var
  text : string;
begin
  // Just 1 data item
  ShowMessageFmt('%s', ['Hello']);

  // A mix of literal text and a data item
  ShowMessageFmt('String = %s', ['Hello']);
  ShowMessage('');

  // Examples of each of the data types
  ShowMessageFmt('Decimal          = %d', [-123]);
  ShowMessageFmt('Exponent         = %e', [12345.678]);
  ShowMessageFmt('Fixed            = %f', [12345.678]);
  ShowMessageFmt('General          = %g', [12345.678]);
  ShowMessageFmt('Number           = %n', [12345.678]);
  ShowMessageFmt('Money            = %m', [12345.678]);
  ShowMessageFmt('Pointer          = %p', [addr(text)]);
  ShowMessageFmt('String           = %s', ['Hello']);
  ShowMessageFmt('Unsigned decimal = %u', [123]);
  ShowMessageFmt('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
  ShowMessageFmt('Padded decimal    = <%7d>', [1234]);

  // With the '-' operator, the data is left justified
  ShowMessageFmt('Justified decimal = <%-7d>', [1234]);

  // The precision value forces 0 padding to the desired size
  ShowMessageFmt('0 padded decimal  = <%.6d>', [1234]);

  // A combination of width and precision
  // Note that width value precedes the precision value
  ShowMessageFmt('Width + precision = <%8.6d>', [1234]);

  // The index value allows the next value in the data array
  // to be changed
  ShowMessageFmt('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.
  ShowMessageFmt('In line           = <%10.4d>', [1234]);
  ShowMessageFmt('Part data driven  = <%*.4d>', [10, 1234]);
  ShowMessageFmt('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>
 
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