Unit Function Summary
System Abs Gives the absolute value of a number (-ve sign is removed)
System Addr Gives the address of a variable, function or procedure
SysUtils AnsiCompareStr Compare two strings for equality
SysUtils AnsiCompareText Compare two strings for equality, ignoring case
StrUtils AnsiContainsStr Returns true if a string contains a substring
StrUtils AnsiEndsStr Returns true if a string ends with a substring
StrUtils AnsiIndexStr Compares a string with a list of strings - returns match index
StrUtils AnsiLeftStr Extracts characters from the left of a string
SysUtils AnsiLowerCase Change upper case characters in a string to lower case
StrUtils AnsiMatchStr Returns true if a string exactly matches one of a list of strings
StrUtils AnsiMidStr Returns a substring from the middle characters of a string
SysUtils AnsiPos Find the position of one string in another
StrUtils AnsiReplaceStr Replaces a part of one string with another
StrUtils AnsiReverseString Reverses the sequence of letters in a string
StrUtils AnsiRightStr Extracts characters from the right of a string
StrUtils AnsiStartsStr Returns true if a string starts with a substring
SysUtils AnsiUpperCase Change lower case characters in a string to upper case
Math ArcCos The Arc Cosine of a number, returned in radians
Math ArcSin The Arc Sine of a number, returned in radians
System ArcTan The Arc Tangent of a number, returned in radians
System Assigned Returns true if a reference is not nil
System BeginThread Begins a separate thread of code execution
Classes Bounds Create a TRect value from top left and size values
StdConvs CelsiusToFahrenheit Convert a celsius temperature into fahrenheit
SysUtils ChangeFileExt Change the extension part of a file name
System Chr Convert an integer into a character
SysUtils CompareStr Compare two strings to see which is greater than the other
SysUtils CompareText Compare two strings for equality, ignoring case
Math CompareValue Compare numeric values with a tolerance
System Concat Concatenates one or more strings into one string
ConvUtils Convert Convert one measurement value to another
System Copy Create a copy of part of a string or an array
System Cos The Cosine of a number
SysUtils CreateDir Create a directory
SysUtils CurrToStr Convert a currency value to a string
SysUtils CurrToStrF Convert a currency value to a string with formatting
SysUtils Date Gives the current date
SysUtils DateTimeToFileDate Convert a TDateTime value to a File date/time format
SysUtils DateTimeToStr Converts TDateTime date and time values to a string
SysUtils DateToStr Converts a TDateTime date value to a string
DateUtils DayOfTheMonth Gives day of month index for a TDateTime value (ISO 8601)
DateUtils DayOfTheWeek Gives day of week index for a TDateTime value (ISO 8601)
DateUtils DayOfTheYear Gives the day of the year for a TDateTime value (ISO 8601)
SysUtils DayOfWeek Gives day of week index for a TDateTime value
DateUtils DaysBetween Gives the whole number of days between 2 dates
DateUtils DaysInAMonth Gives the number of days in a month
DateUtils DaysInAYear Gives the number of days in a year
DateUtils DaySpan Gives the fractional number of days between 2 dates
Math DegToRad Convert a degrees value to radians
SysUtils DeleteFile Delete a file specified by its file name
SysUtils DirectoryExists Returns true if the given directory exists
SysUtils DiskFree Gives the number of free bytes on a specified drive
SysUtils DiskSize Gives the size in bytes of a specified drive
StrUtils DupeString Creates a string containing copies of a substring
SysUtils EncodeDate Build a TDateTime value from year, month and day values
DateUtils EncodeDateTime Build a TDateTime value from day and time values
SysUtils EncodeTime Build a TDateTime value from hour, min, sec and msec values
DateUtils EndOfADay Generate a TDateTime value set to the very end of a day
DateUtils EndOfAMonth Generate a TDateTime value set to the very end of a month
System Eof Returns true if a file opened with Reset is at the end
System Eoln Returns true if the current text file is pointing at a line end
System Exp Gives the exponent of a number
SysUtils ExtractFileDir Extracts the dir part of a full file name
SysUtils ExtractFileDrive Extracts the drive part of a full file name
SysUtils ExtractFileExt Extracts the extension part of a full file name
SysUtils ExtractFileName Extracts the name part of a full file name
SysUtils ExtractFilePath Extracts the path part of a full file name
StdConvs FahrenheitToCelsius Convert a fahrenheit temperature into celsius
SysUtils FileAge Get the last modified date/time of a file without opening it
SysUtils FileDateToDateTime Converts a file date/time format to a TDateTime value
SysUtils FileExists Returns true if the given file exists
SysUtils FileGetAttr Gets the attributes of a file
System FilePos Gives the file position in a binary or text file
SysUtils FileSearch Search for a file in one or more directories
SysUtils FileSetAttr Sets the attributes of a file
SysUtils FileSetDate Set the last modified date and time of a file
System FileSize Gives the size in records of an open file
SysUtils FindClose Closes a successful FindFirst file search
SysUtils FindCmdLineSwitch Determine whether a certain parameter switch was passed
SysUtils FindFirst Finds all files matching a file mask and attributes
SysUtils FindNext Find the next file after a successful FindFirst
SysUtils FloatToStr Convert a floating point value to a string
SysUtils FloatToStrF Convert a floating point value to a string with formatting
SysUtils ForceDirectories Create a new path of directories
SysUtils Format Rich formatting of numbers and text into a string
SysUtils FormatCurr Rich formatting of a currency value into a string
SysUtils FormatDateTime Rich formatting of a TDateTime variable into a string
SysUtils FormatFloat Rich formatting of a floating point number into a string
System Frac The fractional part of a floating point number
SysUtils GetCurrentDir Get the current directory (drive plus directory)
System GetLastError Gives the error code of the last failing Windows API call
System GetMem Get a specified number of storage bytes
System Hi Returns the hi-order byte of a (2 byte) Integer
System High Returns the highest value of a type or variable
DateUtils IncDay Increments a TDateTime variable by + or - number of days
DateUtils IncMillisecond Increments a TDateTime variable by + or - number of milliseconds
DateUtils IncMinute Increments a TDateTime variable by + or - number of minutes
SysUtils IncMonth Increments a TDateTime variable by a number of months
DateUtils IncSecond Increments a TDateTime variable by + or - number of seconds
DateUtils IncYear Increments a TDateTime variable by a number of years
Dialogs InputBox Display a dialog that asks for user text input, with default
Dialogs InputQuery Display a dialog that asks for user text input
System Int The integer part of a floating point number as a float
SysUtils IntToHex Convert an Integer into a hexadecimal string
SysUtils IntToStr Convert an integer into a string
System IOResult Holds the return code of the last I/O operation
Math IsInfinite Checks whether a floating point number is infinite
SysUtils IsLeapYear Returns true if a given calendar year is a leap year
System IsMultiThread Returns true if the code is running multiple threads
Math IsNaN Checks to see if a floating point number holds a real number
SysUtils LastDelimiter Find the last position of selected characters in a string
System Length Return the number of elements in an array or string
System Ln Gives the natural logarithm of a number
System Lo Returns the low-order byte of a (2 byte) Integer
Math Log10 Gives the log to base 10 of a number
System Low Returns the lowest value of a type or variable
SysUtils LowerCase Change upper case characters in a string to lower case
Math Max Gives the maximum of two integer values
Math Mean Gives the average for a set of numbers
Dialogs MessageDlg Displays a message, symbol, and selectable buttons
Dialogs MessageDlgPos Displays a message plus buttons at a given screen position
Math Min Gives the minimum of two integer values
DateUtils MonthOfTheYear Gives the month of the year for a TDateTime value
SysUtils Now Gives the current date and time
System Odd Tests whether an integer has an odd value
System Ord Provides the Ordinal value of an integer, character or enum
System ParamCount Gives the number of parameters passed to the current program
System ParamStr Returns one of the parameters used to run the current program
System Pi The mathematical constant
Classes Point Generates a TPoint value from X and Y values
Classes PointsEqual Compares two TPoint values for equality
System Pos Find the position of one string in another
System Pred Decrement an ordinal variable
Printers Printer Returns a reference to the global Printer object
Dialogs PromptForFileName Shows a dialog allowing the user to select a file
Types PtInRect Tests to see if a point lies within a rectangle
Math RadToDeg Converts a radian value to degrees
System Random Generate a random floating point or integer number
Math RandomRange Generate a random integer number within a supplied range
DateUtils RecodeDate Change only the date part of a TDateTime variable
DateUtils RecodeTime Change only the time part of a TDateTime variable
Classes Rect Create a TRect value from 2 points or 4 coordinates
SysUtils RemoveDir Remove a directory
SysUtils RenameFile Rename a file or directory
System Round Rounds a floating point number to an integer
System SeekEof Skip to the end of the current line or file
System SeekEoln Skip to the end of the current line or file
FileCtrl SelectDirectory Display a dialog to allow user selection of a directory
SysUtils SetCurrentDir Change the current directory
System Sin The Sine of a number
System SizeOf Gives the storage byte size of a type or variable
System Slice Creates a slice of an array as an Open Array parameter
System Sqr Gives the square of a number
System Sqrt Gives the square root of a number
System StringOfChar Creates a string with one character repeated many times
SysUtils StringReplace Replace one or more substrings found within a string
System StringToWideChar Converts a normal string into a WideChar 0 terminated buffer
SysUtils StrScan Searches for a specific character in a constant string
SysUtils StrToCurr Convert a number string into a currency value
SysUtils StrToDate Converts a date string into a TDateTime value
SysUtils StrToDateTime Converts a date+time string into a TDateTime value
SysUtils StrToFloat Convert a number string into a floating point value
SysUtils StrToInt Convert an integer string into an Integer value
SysUtils StrToInt64 Convert an integer string into an Int64 value
SysUtils StrToInt64Def Convert a string into an Int64 value with default
SysUtils StrToIntDef Convert a string into an Integer value with default
SysUtils StrToTime Converts a time string into a TDateTime value
StrUtils StuffString Replaces a part of one string with another
System Succ Increment an ordinal variable
Math Sum Return the sum of an array of floating point values
Math Tan The Tangent of a number
SysUtils Time Gives the current time
SysUtils TimeToStr Converts a TDateTime time value to a string
DateUtils Tomorrow Gives the date tomorrow
SysUtils Trim Removes leading and trailing blanks from a string
SysUtils TrimLeft Removes leading blanks from a string
SysUtils TrimRight Removes trailing blanks from a string
System Trunc The integer part of a floating point number
System UpCase Convert a Char value to upper case
SysUtils UpperCase Change lower case characters in a string to upper case
Variants VarType Gives the current type of a Variant variable
System WideCharToString Copies a null terminated WideChar string to a normal string
SysUtils WrapText Add line feeds into a string to simulate word wrap
DateUtils Yesterday Gives the date yesterday
SysUtils Abort Aborts the current processing with a silent exception
System Append Open a text file to allow appending of text to the end
SysUtils AppendStr Concatenate one string onto the end of another
System Assign Assigns a file handle to a binary or text file
System AssignFile Assigns a file handle to a binary or text file
Printers AssignPrn Treats the printer as a text file - an easy way of printing text
SysUtils Beep Make a beep sound
System BlockRead Reads a block of data records from an untyped binary file
System BlockWrite Writes a block of data records to an untyped binary file
System Break Forces a jump out of a single loop
System ChDir Change the working drive plus path for a specified drive
System Close Closes an open file
System CloseFile Closes an open file
System Continue Forces a jump to the next iteration of a loop
SysUtils DateTimeToString Rich formatting of a TDateTime variable into a string
System Dec Decrement an ordinal variable
SysUtils DecodeDate Extracts the year, month, day values from a TDateTime var.
DateUtils DecodeDateTime Breaks a TDateTime variable into its date/time parts
SysUtils DecodeTime Break a TDateTime value into individual time values
System Delete Delete a section of characters from a string
System Dispose Dispose of storage used by a pointer type variable
System EndThread Terminates a thread with an exit code
System Erase Erase a file
System Exclude Exclude a value in a set variable
System Exit Exit abruptly from a function or procedure
System FillChar Fills out a section of storage with a fill character or byte value
System Flush Flushes buffered text file data to the file
SysUtils FreeAndNil Free memory for an object and set it to nil
System FreeMem Free memory storage used by a variable
System GetDir Get the default directory (drive plus path) for a specified drive
SysUtils GetLocaleFormatSettings Gets locale values for thread-safe functions
System Halt Terminates the program with an optional dialog
System Inc Increment an ordinal variable
System Include Include a value in a set variable
System Insert Insert a string into another string
System MkDir Make a directory
System Move Copy bytes of data from a source to a destination
System New Create a new pointer type variable
FileCtrl ProcessPath Split a drive/path/filename string into its constituent parts
System Randomize Reposition the Random number generator next value
System Read Read data from a binary or text file
System ReadLn Read a complete line of data from a text file
System ReallocMem Reallocate an existing block of storage
System Rename Rename a file
SysUtils ReplaceDate Change only the date part of a TDateTime variable
SysUtils ReplaceTime Change only the time part of a TDateTime variable
System Reset Open a text file for reading, or binary file for read/write
System ReWrite Open a text or binary file for write access
System RmDir Remove a directory
System RunError Terminates the program with an error dialog
System Seek Move the pointer in a binary file to a new record position
System SetLength Changes the size of a string, or the size(s) of an array
System SetString Copies characters from a buffer into a string
Dialogs ShowMessage Display a string in a simple dialog with an OK button
Dialogs ShowMessageFmt Display formatted data in a simple dialog with an OK button
Dialogs ShowMessagePos Display a string in a simple dialog at a given screen position
System Str Converts an integer or floating point number to a string
System Truncate Truncates a file size - removes all data after the current position
System Val Converts number strings to integer and floating point values
System Write Write data to a binary or text file
System WriteLn Write a complete line of data to a text file
System AnsiChar A character type guaranteed to be 8 bits in size
System AnsiString A data type that holds a string of AnsiChars
System Boolean Allows just True and False values
System Byte An integer type supporting values 0 to 255
System Cardinal The basic unsigned integer type
System Char Variable type holding a single character
System Comp A 64 bit signed integer
System Currency A floating point type with 4 decimals used for financial values
System Double A floating point type supporting about 15 digits of precision
System Extended The floating point type with the highest capacity and precision
System Int64 A 64 bit sized integer - the largest in Delphi
System Integer The basic Integer type
System LongInt An Integer whose size is guaranteed to be 32 bits
System LongWord A 32 bit unsigned integer
System PAnsiChar A pointer to an AnsiChar value
System PAnsiString Pointer to an AnsiString value
System PChar A pointer to an Char value
System PCurrency Pointer to a Currency value
System PDateTime Pointer to a TDateTime value
System PExtended Pointer to a Extended floating point value
System PInt64 Pointer to an Int64 value
System Pointer Defines a general use Pointer to any memory based data
System PShortString A pointer to an ShortString value
System PString Pointer to a String value
System PVariant Pointer to a Variant value
System PWideChar Pointer to a WideChar
System PWideString Pointer to a WideString value
System Real A floating point type supporting about 15 digits of precision
System Real48 The floating point type with the highest capacity and precision
System ShortInt An integer type supporting values -128 to 127
System ShortString Defines a string of up to 255 characters
System Single The smallest capacity and precision floating point type
System SmallInt An Integer type supporting values from -32768 to 32767
System String A data type that holds a string of characters
Classes TBits An object that can hold an infinite number of Boolean values
ConvUtils TConvType Defines a measurement type as used by Convert
System TDateTime Data type holding a date and time value
System Text Defines a file as a text file
System TextFile Declares a file type for storing lines of text
SysUtils TFloatFormat Formats for use in floating point number display functions
SysUtils TFormatSettings A record for holding locale values for thread-safe functions
Classes TList General purpose container of a list of objects
System TObject The base class type that is ancestor to all other classes
Dialogs TOpenDialog Displays a file selection dialog
Types TPoint Holds X and Y integer values
Dialogs TPrintDialog Class that creates a printer selection and control dialog
Types TRect Holds rectangle coordinate values
SysUtils TReplaceFlags Defines options for the StringReplace routine
Dialogs TSaveDialog Displays a dialog for selecting a save file name
SysUtils TSearchRec Record used to hold data for FindFirst and FindNext
Classes TStringList Holds a variable length list of strings
SysUtils TSysCharSet Characters used by supplied string parsing functions
System TThreadFunc Defines the function to be called by BeginThread
System Variant A variable type that can hold changing data types
System WideChar Variable type holding a single International character
System WideString A data type that holds a string of WideChars
System Word An integer type supporting values 0 to 65535
System AbstractErrorProc Defines a proc called when an abstract method is called
System CmdLine Holds the execution text used to start the current program
SysUtils CurrencyDecimals Defines decimal digit count in the Format function
SysUtils CurrencyFormat Defines currency string placement in curr display functions
SysUtils CurrencyString The currency string used in currency display functions
SysUtils DateSeparator The character used to separate display date fields
SysUtils DecimalSeparator The character used to display the decimal point
System ErrorAddr Sets the error address when an application terminates
System ExitCode Sets the return code when an application terminates
System FileMode Defines how Reset opens a binary file
System Input Defines the standard input text file
SysUtils LongDateFormat Long version of the date to string format
SysUtils LongDayNames An array of days of the week names, starting 1 = Sunday
SysUtils LongMonthNames An array of days of the month names, starting 1 = January
SysUtils LongTimeFormat Long version of the time to string format
SysUtils NegCurrFormat Defines negative amount formatting in currency displays
Variants Null A variable that has no value
System Output Defines the standard output text file
System RandSeed Reposition the Random number generator next value
System Result A variable used to hold the return value from a function
System Self Hidden parameter to a method - refers to the containing object
SysUtils ShortDateFormat Compact version of the date to string format
SysUtils ShortDayNames An array of days of the week names, starting 1 = Sunday
SysUtils ShortMonthNames An array of days of the month names, starting 1 = Jan
SysUtils ShortTimeFormat Short version of the time to string format
ConvUtils TConvFamily Defines a family of measurement types as used by Convert
SysUtils ThousandSeparator The character used to display the thousands separator
SysUtils TimeAMString Determines AM value in DateTimeToString procedure
SysUtils TimePMString Determines PM value in DateTimeToString procedure
SysUtils TimeSeparator The character used to separate display time fields
SysUtils TwoDigitYearCenturyWindow Sets the century threshold for 2 digit year string conversions
Math Infinity Floating point value of infinite size
System MaxInt The maximum value an Integer can have
System MaxLongInt The maximum value an LongInt can have
SysUtils MinsPerDay Gives the number of minutes in a day
SysUtils MonthDays Gives the number of days in a month
Math NaN Not a real number
System Nil A pointer value that is defined as undetermined
SysUtils SecsPerDay Gives the number of seconds in a day
Variants VarTypeMask Mask for the meta-type part of a Variant variable
$A Determines whether data is aligned or packed
$Align Determines whether data is aligned or packed
$AppType Determines the application type : GUI or Console
$B Whether to short cut and and or operations
$BoolEval Whether to short cut and and or operations
$D Determines whether application debug information is built
$DebugInfo Determines whether application debug information is built
$Define Defines a compiler directive symbol - as used by IfDef
$DefinitionInfo Determines whether application symbol information is built
$Else Starts the alternate section of an IfDef or IfNDef
$EndIf Terminates conditional code compilation
$ExtendedSyntax Controls some Pascal extension handling
$H Treat string types as AnsiString or ShortString
$Hints Determines whether Delphi shows compilation hints
$I Allows code in an include file to be incorporated into a Unit
$IfDef Executes code if a conditional symbol has been defined
$IfNDef Executes code if a conditional symbol has not been defined
$IfOpt Tests for the state of a Compiler directive
$Include Allows code in an include file to be incorporated into a Unit
$IOChecks When on, an IO operation error throws an exception
$L Determines what application debug information is built
$LocalSymbols Determines what application debug information is built
$LongStrings Treat string types as AnsiString or ShortString
$MinEnumSize Sets the minimum storage used to hold enumerated types
$O Determines whether Delphi optimises code when compiling
$Optimization Determines whether Delphi optimises code when compiling
$OverFlowChecks Determines whether Delphi checks integer and enum bounds
$Q Determines whether Delphi checks integer and enum bounds
$R Determines whether Delphi checks array bounds
$RangeChecks Determines whether Delphi checks array bounds
$ReferenceInfo Determines whether symbol reference information is built
$Resource Defines a resource file to be included in the application linking
$UnDef Undefines a compiler directive symbol - as used by IfDef
$Warnings Determines whether Delphi shows compilation warnings
$X Controls some Pascal extension handling
$Y Determines whether application symbol information is built
$Z Sets the minimum storage used to hold enumerated types
Abstract Defines a class method only implemented in subclasses
Default Defines default processing for a property
Dynamic Allows a class method to be overriden in derived classes
System Export Makes a function or procedure in a DLL externally available
Index Principally defines indexed class data properties
Out Identifies a routine parameter for output only
Overload Allows 2 or more routines to have the same name
Override Defines a method that replaces a virtual parent class method
Private Starts the section of private data and methods in a class
Protected Starts a section of class private data accesible to sub-classes
Public Starts an externally accessible section of a class
Published Starts a published externally accessible section of a class
Virtual Allows a class method to be overriden in derived classes
And Boolean and or bitwise and of two arguments
Array A data type holding indexable collections of data
As Used for casting object references
Begin Keyword that starts a statement block
Case A mechanism for acting upon different values of an Ordinal
Class Starts the declaration of a type of object class
Const Starts the definition of fixed data values
Constructor Defines the method used to create an object from a class
Destructor Defines the method used to destroy an object
Div Performs integer division, discarding the remainder
Do Defines the start of some controlled action
DownTo Prefixes an decremental for loop target value
Else Starts false section of if, case and try statements
End Keyword that terminates statement blocks
Except Starts the error trapping clause of a Try statement
File Defines a typed or untyped file
Finally Starts the unconditional code section of a Try statement
For Starts a loop that executes a finite number of times
System Function Defines a subroutine that returns a value
Goto Forces a jump to a label, regardless of nesting
If Starts a conditional expression to determine what to do next
Implementation Starts the implementation (code) section of a Unit
In Used to test if a value is a member of a set
Inherited Used to call the parent class constructor or destructor method
System Interface Used for Unit external definitions, and as a Class skeleton
Is Tests whether an object is a certain class or ascendant
Mod Performs integer division, returning the remainder
Not Boolean Not or bitwise not of one arguments
System Object Allows a subroutine data type to refer to an object method
Of Linking keyword used in many places
On Defines exception handling in a Try Except clause
Or Boolean or or bitwise or of two arguments
Packed Compacts complex data types into minimal storage
System Procedure Defines a subroutine that does not return a value
System Program Defines the start of an application
System Property Defines controlled access to class fields
Raise Raise an exception
Record A structured data type - holding fields of data
Repeat Repeat statements until a ternmination condition is met
Set Defines a set of up to 255 distinct values
Shl Shift an integer value left by a number of bits
Shr Shift an integer value right by a number of bits
Then Part of an if statement - starts the true clause
ThreadVar Defines variables that are given separate instances per thread
To Prefixes an incremental for loop target value
Try Starts code that has error trapping
Type Defines a new category of variable or process
Unit Defines the start of a unit file - a Delphi module
Until Ends a Repeat control loop
Uses Declares a list of Units to be imported
Var Starts the definition of a section of data variables
While Repeat statements whilst a continuation condition is met
With A means of simplifying references to structured variables
Xor Boolean Xor or bitwise Xor of two arguments