Delphi Basics : WrapText command

DelphiBasics

WrapText
Function

Add line feeds into a string to simulate word wrap

SysUtils unit

1	function WrapText(const SourceString {, MaxColumnSize Integer = 45}):string;
2	function WrapText (const SourceString, BreakString string; BreakSet TSysCharSet; MaxColumnSize Integer:string;

Description

The WrapText function effectively splits a line of text SourceString into multiple lines in the returned string.

In actual fact, it simply inserts line breaks into the returned string, so that a display of the string would show as multiple lines.

Version 1

Is the simplest version, allowing a default line break substring (#13#10 - Carriage return + line feed) to be inserted after each set of words fitting MaxColumnSize characters is encountered in the source string. If the max column size is omitted, it defaults to 45.

Version 2

Allows the inserted line break characters BreakString to be inserted after the occurence of a character in the BreakSet is encountered before MaxColumnSize is reached.

If none found BreakString is inserted anyway.

In both cases, words are preserved - never split across lines.

Related commands

Concat		Concatenates one or more strings into one string
Copy		Create a copy of part of a string or an array
Delete		Delete a section of characters from a string
Insert		Insert a string into another string
Move		Copy bytes of data from a source to a destination
StringOfChar		Creates a string with one character repeated many times
StringReplace		Replace one or more substrings found within a string

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Example code : Illustrate the simple version

var
  before, after : string;

begin
  // Set up a long string
  before := 'This is quite a long string, at least 50 chars long';

  // Split it into multiple lines, each 10 characters long
  after := WrapText(before, 10);

  // Show the before and after strings
  ShowMessage(before);
  ShowMessage('');
  ShowMessage(after);
end;

Show full unit code

  This is quite a long string, at least 50 chars long

  This is
  quite a
  long
  string,
  at least
  50 chars
  long

Example code : Wrap on a special control letter

var
  before, after : string;

begin
  // Set up a long string
  before := 'Ten = 10. Eleven = 11. One hundred = 100.';

  // Split it into multiple lines, terminated by a dot
  after := WrapText(before, #13#10, ['.'], 1);

  // Show the before and after strings
  ShowMessage(before);
  ShowMessage('');
  ShowMessage(after);
end;

Show full unit code

  Ten = 10. Eleven = 11. One hundred = 100.

  Ten = 10.
  Eleven = 11.
  One hundred = 100.