System.SysUtils.StrToFloatDef

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Delphi

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

C++

extern DELPHI_PACKAGE System::Extended __fastcall StrToFloatDef(const System::UnicodeString S, const System::Extended Default)/* overload */;

Properties

Type Visibility Source Unit Parent
function public
System.SysUtils.pas
System.SysUtils.hpp
System.SysUtils System.SysUtils

Description

Converts a given string into a floating-point value, with a default error.

Use StrToFloatDef to convert a string, S, to a floating-point value. S must consist of an optional sign (+ or -), a string of digits with an optional decimal point, and an optional mantissa. The mantissa consists of 'E' or 'e' followed by an optional sign (+ or -) and a whole number. Leading and trailing blanks are ignored.

The DecimalSeparator global variable or its TFormatSettings equivalent defines the character that must be used as a decimal point. Thousand separators and currency symbols are not allowed in the string. If S does not contain a valid value, StrToFloatDef returns Default.

The first form of StrToFloatDef is not thread-safe, because it uses localization information contained in global variables. The second form of StrToFloatDef, which is thread-safe, refers to localization information contained in the AFormatSettings parameter. Before calling the thread-safe form of StrToFloatDef, you must populate AFormatSettings with localization information. To populate AFormatSettings with a set of default locale values, call TFormatSettings.Create.

See Also