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Strtoint - 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. 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 Example code : Converting decimal and hexadecimal numbers 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; Show 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