常用函數

String

System

function Copy(S: String; Index: Integer; Count: Integer): string;

 

System.SysUtils

function StringReplace(const S, OldPattern, NewPattern: string; Flags: TReplaceFlags): string;

function FormatDateTime(const Format: string; DateTime: TDateTime): string;

function FormatFloat(const Format: string; Value: Extended): string;

function FormatCurr(const Format: string; Value: Currency): string;

function Trim(const S: string): string; 

function TrimLeft(const S: string): string; overload;

function TrimRight(const S: string): string; overload;

function QuotedStr(const S: string): string; overload;

 比對字串 (不區分大小寫)

function CompareText(const S1, S2: string): Integer; 

 

function UpperCase(const S: string): string; 

function UpperCase(const S: string; LocaleOptions: TLocaleOptions): string;

function LowerCase(const S: string): string; overload;

function LowerCase(const S: string; LocaleOptions: TLocaleOptions): string;

function Languages: TLanguages;

System.StrUtils

 回傳Text存在於Array裡的索引值 (區分大小寫)

function IndexStr(const AText: string; const AValues: array of string): Integer;

回傳Text存在於Array裡的索引值 (不區分大小寫)

function IndexText(const AText: string; const AValues: array of string): Integer; 

 

function LeftStr(const AText: string; const ACount: Integer): string; overload;

function RightStr(const AText: string; const ACount: Integer): string; overload;

function MidStr(const AText: string; const AStart, ACount: Integer): string; overload;

function ReverseString(const AText: string): string;

function SplitString(const S, Delimiters: string): TStringDynArray;

 

function IfThen(AValue: Boolean; const ATrue: string; AFalse: string = ''): string; overload;  

Integer / Float

System

是否為奇數

function Odd(X: Integer): Boolean;

 

procedure Inc(var X: Integer); 

procedure Inc(var X: Integer; N: Integer);

 

System.SysUtils

function StrToIntDef(const S: string; const Default: Extended): Extended;

function StrToFloatDef(const S: string; const Default: Extended): Extended;

function TryStrToFloat(const S: string; out Value: Extended): Boolean;

function TryStrToCurr(const S: string; out Value: Currency): Boolean;

function TryStrToInt(const S: string; out Value: Integer): Boolean; overload;

 

System.Math

平方

function Power(const Base, Exponent: Double): Double;

 

將變數向上捨入至正無窮大。

function Ceil(const X: Double): Integer; 

 

將變數向負無窮方向舍入。

function Floor(const X: Double): Integer;  

 

Form.Width / 2 回傳浮點數

Form.Width div 2 回傳整數值 (不計小數)

function Max(const A, B: Integer): Integer; overload;

function MaxValue(const Data: array of Double): Double; overload;

function MaxIntValue(const Data: array of Integer): Integer;

function Min(const A, B: Integer): Integer; overload;

function MinValue(const Data: array of Double): Double; overload;

function MinIntValue(const Data: array of Integer): Integer;

function InRange(const AValue, AMin, AMax: Int64): Boolean; overload;

取整數

function Int(const X: Extended): Extended;

取小數

function Frac(const X: Extended): Extended;

判斷正/負號

function Sign(const AValue: Integer): TValueSign; 

Array中的平均值

function Mean(const Data: array of Single): Single;

function IfThen(AValue: Boolean; const ATrue: Integer; const AFalse: Integer = 0): Integer; overload;

Datetime

System.DateUtils

function IsPM(const AValue: TDateTime): Boolean; 
function IsAM(const AValue: TDateTime): Boolean;
function IsValidDate(const AYear, AMonth, ADay: Word): Boolean;
 
傳回指定 TDateTime 值所在年份的週數。
function WeeksInYear(const AValue: TDateTime): Word;
 
傳回指定年份的週數。
function WeeksInAYear(const AYear: Word): Word;       
 
傳回指定 TDateTime 值所在年份的天數。
function DaysInYear(const AValue: TDateTime): Word; 
 
傳回指定年份的天數。
function DaysInAYear(const AYear: Word): Word; 
 
傳回指定月份的天數。
function DaysInMonth(const AValue: TDateTime): Word;
 
傳回指定年份的指定月份的天數。
function DaysInAMonth(const AYear, AMonth: Word): Word;

 

function Today: TDateTime;
function Yesterday: TDateTime;
function Tomorrow: TDateTime;

 

function YearOf(const AValue: TDateTime): Word;
function MonthOf(const AValue: TDateTime): Word;
function WeekOf(const AValue: TDateTime): Word;           
function DayOf(const AValue: TDateTime): Word;
function HourOf(const AValue: TDateTime): Word;
function MinuteOf(const AValue: TDateTime): Word;
function SecondOf(const AValue: TDateTime): Word;
function MilliSecondOf(const AValue: TDateTime): Word;
function StartOfTheMonth(const AValue: TDateTime): TDateTime;
function EndOfTheMonth(const AValue: TDateTime): TDateTime;
function StartOfAMonth(const AYear, AMonth: Word): TDateTime;
function EndOfAMonth(const AYear, AMonth: Word): TDateTime;
function StartOfTheWeek(const AValue: TDateTime): TDateTime; 
function EndOfTheWeek(const AValue: TDateTime): TDateTime;  
function StartOfAWeek(const AYear, AWeekOfYear: Word;const ADayOfWeek: Word = 1): TDateTime;
function EndOfAWeek(const AYear, AWeekOfYear: Word;const ADayOfWeek: Word = 7): TDateTime;
 
function YearsBetween(const ANow, AThen: TDateTime): Integer;
function MonthsBetween(const ANow, AThen: TDateTime): Integer;
function WeeksBetween(const ANow, AThen: TDateTime): Integer;
function DaysBetween(const ANow, AThen: TDateTime): Integer;
function HoursBetween(const ANow, AThen: TDateTime): Int64;
function MinutesBetween(const ANow, AThen: TDateTime): Int64;
function SecondsBetween(const ANow, AThen: TDateTime): Int64;
function MilliSecondsBetween(const ANow, AThen: TDateTime): Int64;

 

function IncYear(const AValue: TDateTime; const ANumberOfYears: Integer = 1): TDateTime; inline;

function IncWeek(const AValue: TDateTime;const ANumberOfWeeks: Integer = 1): TDateTime; inline;

指定天數偏移的日期 

function IncDay(const AValue: TDateTime; const ANumberOfDays: Integer = 1): TDateTime; inline;
 
function IncHour(const AValue: TDateTime; const ANumberOfHours: Int64 = 1): TDateTime; inline;
function IncMinute(const AValue: TDateTime; const ANumberOfMinutes: Int64 = 1): TDateTime; 

function IncSecond(const AValue: TDateTime; const ANumberOfSeconds: Int64 = 1): TDateTime;

function IncMilliSecond(const AValue: TDateTime; const ANumberOfMilliSeconds:Int64 = 1): TDateTime;

File/Fold

System.SysUtil

資料夾是否存在.

function DirectoryExists(const Directory: string; FollowLink: Boolean = True): Boolean;

檔案是否存在

function FileExists(const FileName: string; FollowLink: Boolean = True): Boolean;

檔案放置的資料夾

function ExtractFileDir(const FileName: string): string;

檔案放置的路徑

function ExtractFilePath(const FileName: string): string;

檔案放置的磁碟代號

function ExtractFileDrive(const FileName: string): string;

檔案名稱

function ExtractFileName(const FileName: string): string;

變更副檔名

function ChangeFileExt(const FileName, Extension: string): string;

檔案是否唯讀

function FileIsReadOnly(const FileName: string): Boolean;

檔案設定唯讀

function FileSetReadOnly(const FileName: string; ReadOnly: Boolean): Boolean;

刪除檔案

function DeleteFile(const FileName: string): Boolean;

檔案名稱更名

function RenameFile(const OldName, NewName: string): Boolean;

檔案搜尋

function FileSearch(const Name, DirList: string): string;

目前的使用路徑

function GetCurrentDir: string;

設定目前的使用路徑

function SetCurrentDir(const Dir: string): Boolean;

建立資料夾(樹狀)

function ForceDirectories(Dir: string): Boolean;

建立資料夾

function CreateDir(const Dir: string): Boolean;

移除資料夾

function RemoveDir(const Dir: string): Boolean;