| 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.
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| Notes |
The EConvertError exception is thrown if there are errors in IntegerString, such as trailing blanks, decimal points, invalid decimal or hexadecimal characters.
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| Related commands |
| Integer |
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The basic Integer type |
| IntToStr |
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Convert an integer into a string |
| StrToInt64 |
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Convert an integer string into an Int64 value |
| StrToInt64Def |
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Convert a string into an Int64 value with default |
| StrToIntDef |
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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.
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| Hide full unit code |
A : 32
B : 100
C : -12
D : 30
E : -30
F : 120
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| 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('$FG'); // 'G' is an invalid hexadecimal digit
except
on Exception : EConvertError do
ShowMessage(Exception.Message);
end;
end;
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| Show full unit code |
'100 ' is not a valid integer value
'$FG' is not a valid integer value
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