DelphiBasics
 StrToIntFunction Convert an integer string into an Integer value SysUtils unit
 function StrToInt ( IntegerString : string ) : Integer;
Description
The StrToInt function converts an Integer string, IntegerString such as '123' into an Integer.

It supports +ve and -ve numbers, and hexadecimal numbers, as prefixed by \$ or 0x.

Note that for Delphi 7 and possibly other versions of Delphi, you may omit the 0 before the x for hexadecimal values.
Notes
The EConvertError exception is thrown if there are errors in IntegerString, such as trailing blanks, decimal points, invalid decimal or hexadecimal characters.
Related commands
 Integer The basic Integer type IntToStr Convert an integer into a string StrToInt64 Convert an integer string into an Int64 value StrToInt64Def Convert a string into an Int64 value with default StrToIntDef Convert a string into an Integer value with default
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 Example code : Converting decimal and hexadecimal numbers // Full Unit code.// -----------------------------------------------------------// You must store this code in a unit called Unit1 with a form// called Form1 that has an OnCreate event called FormCreate. unit Unit1; interface uses  SysUtils,   // Unit containing the StrToInt command  Forms, Dialogs; type  TForm1 = class(TForm)    procedure FormCreate(Sender: TObject);  end; var  Form1: TForm1; implementation{\$R *.dfm} // Include form definitions procedure TForm1.FormCreate(Sender: TObject); var   A, B, C, D, E, F : Integer; begin   A := 32;  B := StrToInt('100');    // '100' string converted to 100 integer  C := StrToInt('  -12');  // Leading blanks are ignored  D := StrToInt('\$1E');    // Hexadecimal values start with a '\$'  E := StrToInt('-0x1E');  // ... or with a '0x'  F := A + B + C + D + E;  // Lets add up all these integers   ShowMessage('A : '+IntToStr(A));   ShowMessage('B : '+IntToStr(B));   ShowMessage('C : '+IntToStr(C));   ShowMessage('D : '+IntToStr(D));   ShowMessage('E : '+IntToStr(E));   ShowMessage('F : '+IntToStr(F)); end; end. Hide full unit code A :  32   B : 100   C : -12   D :  30   E : -30   F : 120 Example code : Catching string to integer conversion errors var   A : Integer; begin  // We will catch conversion errors   try    A := StrToInt('100 ');    // Trailing blanks are not supported   except     on Exception : EConvertError do       ShowMessage(Exception.Message);   end;   try    A := StrToInt('\$FG');    // 'G' is an invalid hexadecimal digit   except     on Exception : EConvertError do       ShowMessage(Exception.Message);   end; end; Show full unit code '100 ' is not a valid integer value   '\$FG' is not a valid integer value
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