| Description |
Attempts to parse the Value string into a value between -32768 and 32767, returning a Int16 object with this value.
The Style parameter determines the allowed number content. It is an enumerated type that is treated as a set of flags (it has the [Flags] attribute). This means that multiple values may be set, using logical or. The possible values are :
| AllowCurrencySymbol | Allow for ?,$ ... |
| AllowExponent | E+000 format |
| AllowThousands | For example : 1,000,000 |
| AllowDecimalPoint | For example : 123.456 |
| AllowParentheses | For example (1234) |
| AllowTrailingSign | For example : 123- |
| AllowLeadingSign | For example : -123 |
| AllowTrailingWhite | Allow trailing blanks |
| AllowLeadingWhite | Allow leading blanks |
| AllowHexSpecifier | For example : 0x2bcd |
Note that not all of these allowances are meaningful for Int16 values.
The FormatProvider option allows for customised formatting and is beyond the scope of Delphi Basics.
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| | Notes | Warning : An exception is thrown if the parse encounters unexpected characters.
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| | References | NumberStyles
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| Microsoft MSDN Links |
System
System.Int16
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| A simple example |
// Full Unit code.
// -------------------------------------------------------------
// Create a new WinForm application, double click the form to
// create an OnLoad event, and then replace the WinForm unit
// with this text.
unit WinForm;
interface
uses
System.Drawing, System.Collections, System.ComponentModel,
System.Windows.Forms, System.Data;
type
TWinForm = class(System.Windows.Forms.Form)
\{REGION 'Designer Managed Code'\} // Note that REGION and ENREGION should be prefixed by a dollar sign
strict private
///
/// Required designer variable.
///
Components: System.ComponentModel.Container;
///
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///
procedure InitializeComponent;
procedure TWinForm_Load(sender: System.Object; e: System.EventArgs);
{ENDREGION}
strict protected
///
/// Clean up any resources being used.
///
procedure Dispose(Disposing: Boolean); override;
private
{ Private Declarations }
public
constructor Create;
end;
[assembly: RuntimeRequiredAttribute(TypeOf(TWinForm))]
implementation
\{REGION 'Windows Form Designer generated code'\}
///
/// Required method for Designer support -- do not modify
/// the contents of this method with the code editor.
///
procedure TWinForm.InitializeComponent;
begin
//
// TWinForm
//
Self.AutoScaleBaseSize := System.Drawing.Size.Create(5, 13);
Self.ClientSize := System.Drawing.Size.Create(292, 266);
Self.Name := 'TWinForm';
Self.Text := 'WinForm';
Include(Self.Load, Self.TWinForm_Load);
end;
{ENDREGION}
procedure TWinForm.Dispose(Disposing: Boolean);
begin
if Disposing then
begin
if Components <> nil then
Components.Dispose();
end;
inherited Dispose(Disposing);
end;
constructor TWinForm.Create;
begin
inherited Create;
//
// Required for Windows Form Designer support
//
InitializeComponent;
//
// TODO: Add any constructor code after InitializeComponent call
//
end;
procedure TWinForm.TWinForm_Load(sender: System.Object; e: System.EventArgs);
program Project1;
{$APPTYPE CONSOLE}
uses
System.Globalization;
var
intStr : String;
result : Integer;
begin
intStr := '23';
result := System.Int16.Parse(intStr);
Console.WriteLine('''' + intStr + ''' parses to {0}', result.ToString);
Console.ReadLine;
end.
end. | | Hide full unit code | '23' parses to 23
| | | Using NumberStyles | program Project1;
{$APPTYPE CONSOLE}
uses
System.Globalization;
var
style : NumberStyles;
intStr : String;
result : Integer;
begin
// Allow for hex values and leading/trailing blanks
style := NumberStyles.AllowLeadingWhite or
NumberStyles.AllowTrailingWhite or
NumberStyles.AllowHexSpecifier;
intStr := ' 12AB '; // Hex 12AB = 4779
result := System.Int16.Parse(intStr, style);
Console.WriteLine('''' + intStr + ''' parses to {0}', result.ToString);
// Or more simply using one combined number style value
style := NumberStyles.HexNumber;
intStr := ' FF00 '; // Hex FF00 = -256
result := System.Int16.Parse(intStr, style);
Console.WriteLine('''' + intStr + ''' parses to {0}', result.ToString);
Console.ReadLine;
end.
| | Show full unit code | ' 12AB ' parses to 4779
' FF00 ' parses to -256
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