added additional checks

VECTO/GUI/IHPCForm.vb

@@ -17,13 +17,7 @@ Public Class IHPCForm
 #Region "Set JSON Data"
 
     Public Sub ReadIHPCFile(file As String)
-
-        Dim inputProvider = New JSONComponentInputData(file, Nothing)
-        Dim ihpcData = inputProvider.ElectricMachines.Entries.First().ElectricMachine
-
-        If IsNothing(ihpcData) Then
-            Return
-        End If
+        Dim ihpcData = JSONInputDataFactory.ReadIHPCEngineeringInputData(file, True)
 
         tbModel.Text = ihpcData.Model
         tbInertia.Text = ihpcData.Inertia.ToGUIFormat()

VECTO/GUI/VehicleForm.vb

@@ -684,8 +684,6 @@ Public Class VehicleForm
 
 				tcVehicleComponents.TabPages.Remove(tpElectricMachine)
 				tcVehicleComponents.TabPages.Remove(tpGensetComponents)
-
-		        'IEPC
 				tcVehicleComponents.TabPages.Remove(tpIEPC)
 
 			Case Else
@@ -1538,6 +1536,14 @@ Public Class VehicleForm
 		Dim f = FileRepl(tbIEPCFilePath.Text, GetPath(_vehFile))
 
 		IEPCForm.JobDir = GetPath(_vehFile)
+
+		If Not Trim(f) = "" Then
+			If Not File.Exists(f) Then
+				MsgBox("File not found!")
+				Exit Sub
+			End If
+		End If
+
 		If Not IEPCForm.Visible Then
 			IEPCForm.NewIEPC()
 			IEPCForm.Show()
@@ -1565,6 +1571,13 @@ Public Class VehicleForm
 		Dim f = FileRepl(tbIHPCFilePath.Text, GetPath(_vehFile))
 
 		IHPCForm.JobDir = GetPath(_vehFile)
+	    If Not Trim(f) = "" Then
+	        If Not File.Exists(f) Then
+	            MsgBox("File not found!")
+	            Exit Sub
+	        End If
+	    End If
+
 		If Not IHPCForm.Visible Then
 			IHPCForm.ClearIHPC()
 			IHPCForm.Show()

VectoCore/VectoCore/InputData/FileIO/JSON/JSONInputDataFactory.cs

@@ -258,5 +258,19 @@ namespace TUGraz.VectoCore.InputData.FileIO.JSON
 					throw new VectoException("Engineering IEPC: Unsupported FileVersion. Got {0}", version);
 			}
 		}
+
+		public static IElectricMotorEngineeringInputData ReadIHPCEngineeringInputData(string filename,
+			bool tolerateMissing = false)
+		{
+			var json = ReadFile(filename);
+			var version = ReadVersion(json);
+			switch (version)
+			{
+				case 5:
+					return ReadElectricMotorData(filename, tolerateMissing);
+				default:
+					throw new VectoException("Engineering IHPC: Unsupported FileVersion. Got {0}", version);
+			}
+		}
 	}
 }