ReturnStrMethod

Applies to:Fast Math Parser

Class:uCalc.Callback

Sets the return value of a uCalc.Callback function as a String

Syntax

ReturnStr(Value)

Parameters

Value

String

String value that your callback returns

Returns

Nothing

Remarks

When you define a callback function with DefineFunction that returns a string, do it with ReturnStr.

Example 1: Returning a string (from a callback)

VB
C#
Delphi
C++
VC++.NET


          
Sub TwiceStrCB(ByVal ExprPartPtr As IntPtr)
   Dim ExprPart As New uCalc.Callback(ExprPartPtr)
   ExprPart.ReturnStr(ExprPart.ArgStr(1) + ExprPart.ArgStr(1))
End Sub

Sub TwiceStr()
   uc.DefineFunction("Twice(Txt As String) As String", uc.PinAddr(AddressOf TwiceStrCB))
   Console.WriteLine(uc.EvalStr("Twice('Ha')")) ' Returns "HaHa"
End Sub


          
static void TwiceStrCB(IntPtr ExprPartPtr) {
   var ExprPart = New uCalc.Callback(ExprPartPtr);
   ExprPart.ReturnStr(ExprPart.ArgStr(1) + ExprPart.ArgStr(1));
}

static void TwiceStr() {
   uc.DefineFunction("Twice(Txt As String) As String", uc.PinAddr(TwiceStrCB));
   Console.WriteLine(uc.EvalStr("Twice('Ha')")); // Returns "HaHa";
}


          
procedure TwiceStrCB(ExprPartPtr: System.Pointer);
begin
   
//var ExprPart: uCalc.CreateCallback(ExprPartPtr);
   ExprPart.ReturnStr(ExprPart.ArgStr(1) + ExprPart.ArgStr(1));
End;

procedure TwiceStr();
begin
   
   uc.DefineFunction('Twice(Txt As String) As String', TwiceStrCB);
   WriteLn(uc.EvalStr('Twice("Ha")')); // Returns 'HaHa';
End;


          
void _stdcall TwiceStrCB(uCalcPtr ExprPartPtr) {
   auto ExprPart = uCalc::Callback(ExprPartPtr);
   ExprPart.ReturnStr(ExprPart.ArgStr(1) + ExprPart.ArgStr(1));
}

void TwiceStr() {
   uc.DefineFunction("Twice(Txt As String) As String", TwiceStrCB);
   cout << uc.EvalStr("Twice('Ha')") << endl; // Returns "HaHa";
}


          
static void TwiceStrCB(uCalcPtr ExprPartPtr) {
   auto ExprPart = uCalc::Callback(ExprPartPtr);
   ExprPart.ReturnStr(ExprPart.ArgStr(1) + ExprPart.ArgStr(1));
}

static void TwiceStr() {
   uc.DefineFunction("Twice(Txt As String) As String", ucPinAddr(TwiceStrCB));
   Console::WriteLine(uc.EvalStr("Twice('Ha')")); // Returns "HaHa";
}

DLL import code

VB
C#
Delphi
C++
VC++.NET


            <DllImport(uCalcDLL, CharSet:=CharSet.Ansi, CallingConvention:=CallingConvention.Cdecl, EntryPoint:="ReturnStr")> _

Private Sub ReturnStr__(ByVal ExprPartHandle As IntPtr,ByVal Value As String)
End Sub


            [DllImport(uCalcDLL, CharSet=CharSet.Ansi, CallingConvention=CallingConvention.Cdecl, EntryPoint="ReturnStr")]

protected static extern  void ReturnStr_(IntPtr ExprPartHandle, string Value);


            {DLLImport}procedure ReturnStr__(ExprPartHandle: System.Pointer;Value: AnsiString); cdecl; external uCalcDLL name 'ReturnStr';


            typedef  void (* __ReturnStr)(void *ExprPartHandle, CONSTCHAR Value );


            [DllImport(uCalcLib, CharSet=CharSet::Ansi, CallingConvention=CallingConvention::Cdecl, EntryPoint = "ReturnStr")]

static void ReturnStr_(void *  ExprPartHandle, MARSHALSTR Value);