A practical example using an error handler to provide a custom, user-friendly message when an invalid operation occurs.

ID: 407

See: TrapOnInvalid = [bool] 
				
					using uCalcSoftware;

var uc = new uCalc();

static void MyErrorHandler(Handle_uCalc h) {
   var uc = new uCalc(h);
   // Check if the specific 'FloatInvalid' error was raised
   if (uc.Error.Code == ErrorCode.FloatInvalid) {
      Console.WriteLine("Error: The calculation resulted in an invalid number (e.g., square root of a negative).");
      // Stop further processing
      uc.Error.Response = ErrorHandlerResponse.Abort;
   }
}


// Register the custom error handler
uc.Error.AddHandler(MyErrorHandler);

// Tell uCalc to raise an error instead of returning 'nan'
uc.Error.TrapOnInvalid = true;

// This will now trigger our custom error handler's message
uc.EvalStr("sqrt(-4)");
				
			
Error: The calculation resulted in an invalid number (e.g., square root of a negative).
Explore 600+ other examples
				
					#include <iostream>
#include "uCalc.h"

using namespace std;
using namespace uCalcSoftware;

void ucalc_call MyErrorHandler(Handle_uCalc h) {
   auto uc = uCalc(h);
   // Check if the specific 'FloatInvalid' error was raised
   if (uc.Error().Code() == ErrorCode::FloatInvalid) {
      cout << "Error: The calculation resulted in an invalid number (e.g., square root of a negative)." << endl;
      // Stop further processing
      uc.Error().Response(ErrorHandlerResponse::Abort);
   }
}

int main() {
   uCalc uc;
   // Register the custom error handler
   uc.Error().AddHandler(MyErrorHandler);

   // Tell uCalc to raise an error instead of returning 'nan'
   uc.Error().TrapOnInvalid(true);

   // This will now trigger our custom error handler's message
   uc.EvalStr("sqrt(-4)");
}
				
			
Error: The calculation resulted in an invalid number (e.g., square root of a negative).
Explore 600+ other examples
				
					Imports System
Imports uCalcSoftware
Public Module Program
   
   Public Sub MyErrorHandler(ByVal h As Handle_uCalc)
      Dim uc As New uCalc(h)
      '// Check if the specific 'FloatInvalid' error was raised
      If uc.Error.Code = ErrorCode.FloatInvalid Then
         Console.WriteLine("Error: The calculation resulted in an invalid number (e.g., square root of a negative).")
         '// Stop further processing
         uc.Error.Response = ErrorHandlerResponse.Abort
      End If
   End Sub
   
   Public Sub Main()
      Dim uc As New uCalc()
      '// Register the custom error handler
      uc.Error.AddHandler(AddressOf MyErrorHandler)
      
      '// Tell uCalc to raise an error instead of returning 'nan'
      uc.Error.TrapOnInvalid = true
      
      '// This will now trigger our custom error handler's message
      uc.EvalStr("sqrt(-4)")
   End Sub
End Module
				
			
Error: The calculation resulted in an invalid number (e.g., square root of a negative).
Explore 600+ other examples