System.SysUtils.TryStrToFloat
Delphi
function TryStrToFloat(const S: string; out Value: Extended): Boolean;
function TryStrToFloat(const S: string; out Value: Extended; const AFormatSettings: TFormatSettings): Boolean;
function TryStrToFloat(const S: string; out Value: Double): Boolean;
function TryStrToFloat(const S: string; out Value: Double; const AFormatSettings: TFormatSettings): Boolean;
function TryStrToFloat(const S: string; out Value: Single): Boolean;
function TryStrToFloat(const S: string; out Value: Single; const AFormatSettings: TFormatSettings): Boolean;
C++
extern DELPHI_PACKAGE bool __fastcall TryStrToFloat(const System::UnicodeString S, /* out */ System::Extended &Value)/* overload */;
Properties
Type | Visibility | Source | Unit | Parent |
---|---|---|---|---|
function | public | System.SysUtils.pas System.SysUtils.hpp |
System.SysUtils | System.SysUtils |
Description
Converts a given string to a floating-point value, with a Boolean success code.
Use TryStrToFloat 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 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, TryStrToFloat returns False
; it returns True
otherwise.
TryStrToFloat places the result in Value
, and returns True if the conversion was successful, False otherwise.
The first three forms of TryStrToFloat are not thread-safe, because they use localization information contained in global variables. The second three forms of TryStrToFloat, which are thread-safe, refer to localization information contained in the AFormatSettings
parameter. Before calling the thread-safe forms of TryStrToFloat, you must populate AFormatSettings
with localization information. To populate AFormatSettings
with a set of default locale values, call TFormatSettings.Create.