Stackoverflow error C# with getter and setter - c#

This is the working class:
namespace Lite
{
public class Spec
{
public int ID { get; set; }
public string Name { get; set; }
public string FriendlyName { get; set; }
public int CategoryID { get; set; }
public int Width { get; set; }
public int Height { get; set; }
public string UOM { get; set; }
public int Pagination { get; set; }
public int ColoursFront { get; set; }
public int ColoursBack { get; set; }
public string Material { get; set; }
public int GSM { get; set; }
public string GSMUOM { get; set; }
public bool Seal { get; set; }
public Spec(int ID)
{
using (CrystalCommon.MainContext db = new CrystalCommon.MainContext())
{
var q = (from c in db.tblSpecifications where c.id == ID select c).SingleOrDefault();
if (q != null)
loadByRec(q);
}
}
public Spec(CrystalCommon.tblSpecification Rec)
{
loadByRec(Rec);
}
public void loadByRec(CrystalCommon.tblSpecification Rec)
{
this.ID = Rec.id;
this.Name = Rec.Title;
this.Width = Convert.ToInt32(Rec.FinishedSizeW.Value);
this.Height = Convert.ToInt32(Rec.FinishedSizeL.Value);
this.UOM = Rec.FlatSizeUOM;
this.Pagination = Rec.TxtPagination.Value;
this.ColoursFront = Convert.ToInt32(Rec.TxtColsF.Value);
this.ColoursBack = Convert.ToInt32(Rec.TxtColsB.Value);
this.Material = Rec.TxtMaterial;
this.GSM = Rec.TxtGSM.Value;
this.GSMUOM = Rec.txtGsmUnit;
this.Seal = Rec.TxtSeal.Value == 1;
}
public string displayDimensions()
{
return Width + " x " + Height + " " + UOM;
}
}
}
Then I try and modify the Name getter and setter:
namespace Lite
{
public class Spec
{
public int ID { get; set; }
// User friendly name if available otherwise fall back on spec name
public string Name { get {
if (null != FriendlyName)
return FriendlyName;
else
return Name;
}
set
{
Name = value;
}
}
public string FriendlyName { get; set; }
public int CategoryID { get; set; }
public int Width { get; set; }
public int Height { get; set; }
public string UOM { get; set; }
public int Pagination { get; set; }
public int ColoursFront { get; set; }
public int ColoursBack { get; set; }
public string Material { get; set; }
public int GSM { get; set; }
public string GSMUOM { get; set; }
public bool Seal { get; set; }
public Spec(int ID)
{
using (CrystalCommon.MainContext db = new CrystalCommon.MainContext())
{
var q = (from c in db.tblSpecifications where c.id == ID select c).SingleOrDefault();
if (q != null)
loadByRec(q);
}
}
public Spec(CrystalCommon.tblSpecification Rec)
{
loadByRec(Rec);
}
public void loadByRec(CrystalCommon.tblSpecification Rec)
{
this.ID = Rec.id;
this.Name = Rec.Title;
this.Width = Convert.ToInt32(Rec.FinishedSizeW.Value);
this.Height = Convert.ToInt32(Rec.FinishedSizeL.Value);
this.UOM = Rec.FlatSizeUOM;
this.Pagination = Rec.TxtPagination.Value;
this.ColoursFront = Convert.ToInt32(Rec.TxtColsF.Value);
this.ColoursBack = Convert.ToInt32(Rec.TxtColsB.Value);
this.Material = Rec.TxtMaterial;
this.GSM = Rec.TxtGSM.Value;
this.GSMUOM = Rec.txtGsmUnit;
this.Seal = Rec.TxtSeal.Value == 1;
}
public string displayDimensions()
{
return Width + " x " + Height + " " + UOM;
}
}
}
On my computer this compiles fine, but the server seems to crash when it runs. (First version works fine). My colleague compiled it on his machine and it threw a "Stack overflow error" apparently, but he's not around for me to get specifics on that right now.
Am I applying the getter correctly here?

This is an endless loop:
public string Name { get {
...
set
{
Name = value;
}
}
The setter will call itself repeatedly until you get the Stack overflow exception.
usually you have a backing variable, so it ends up like this
private string name;
public string Name {
get {
if (null != FriendlyName)
return FriendlyName;
else
return name;
}
set {
name = value;
}
}

Your set is referencing the property itself, and your get is referencing the property itself, both of these will cause a potentially endless loop leading to a StackOverflowException (no more stack space to push the current call into). You need to use a backing field:
private string _name;
public string Name
{
get
{
if (null != FriendlyName)
return FriendlyName;
else
return _name;
}
set
{
_name = value;
}
}
It looks as though you tried to turn an auto-property into a manual one. Auto-properties (public string Name { get; set; }) work because the compiler will create the backing field itself.
As a learning exercise, if you step through with the debugger and step into return Name or Name = value you will see first hand the code going back into the property you are already in.

This is much better.
string _name = "";
public string Name
{
get { return FriendlyName ?? _name; }
set { _name = value; }
}

One of your properties gets and sets itself, see:
public string Name
{
get {
if (null != FriendlyName)
return FriendlyName;
else
return Name; //<-- StackOverflow
}
set
{
Name = value; //<-- StackOverflow
}
}

You have a getter for Name, that calls the property Name, which will call the getter for Name, etc. You need a private field to back the property, and you need to access that backing field in your getter instead.

public string Name { get {
if (null != FriendlyName)
return FriendlyName;
else
return Name;
}
set
{
Name = value;
}
}
Name in the get/set refers to the property. You will need to define a backing field and use that.

If FriendlyName is null then the Name getter attempts to get the value from the Name getter - i.e. it loops. This is what causes the stack overflow.

No you should use a backing field. The error is in the else
public string Name { get {
if (null != FriendlyName)
return FriendlyName;
else
return Name;//error, you're calling the property getter again.
}

Related

CsvHelper Looking for Non-existent Columns

The propblem: There is no "Name" field in the object or csv file, yet CsVHelper keeps looking for "Name" in the header. So why is it tripping there and what are some fixes?
When trying to build objects from a csv file, the following error comes up:
CsvHelper.HeaderValidationException: Header with name 'Name' was not found. If you are expecting some headers to be missing and want to ignore this validation, set the configuration HeaderValidated to null. You can also change the functionality to do something else, like logging the issue.
at CsvHelper.Configuration.ConfigurationFunctions.HeaderValidated(Boolean isValid, String[] headerNames, Int32 headerNameIndex, ReadingContext context)
I have tried setting HeaderValidated to null, but got the same results.
The header of the csv:
Id|Title|Description|AssignedToUserId|SourceUserId|DateCreated|DateAssigned|DateCompleted|Notes
The parsing code:
private static IEnumerable<T> GetCSVData<T>(string fullFileName)
{
PrintMembers<T>();
using (var reader = new StreamReader(fullFileName))
{
using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
{
csv.Configuration.HasHeaderRecord = true;
csv.Configuration.IncludePrivateMembers = false;
csv.Parser.Configuration.Delimiter = "|";
var records = csv.GetRecords<T>().ToList();
return records;
}
}
}
A quick function for listing the public properties and fields of the class (T) being passed in outputs the following:
Properties...
Id
AssignedToUserId
SourceUserId
Title
Description
AssignedTo
Source
DateCreated
DateAssigned
DateCompleted
RelatedTasks
Notes
Fields...
[None]
They all have getters and setters.
EDIT
The IntermediateTask is the generic being fed into GetCSVData(). It has a default constructor. IntermediateTask is internal, but is in the same assembly as GetCSVData().
Code for the class(es) in question:
internal class IntermediateTask : Task
{
private int _Id;
new public int Id
{
get { return _Id; }
set { _Id = value; }
}
private int _AssignedToUserId;
public int AssignedToUserId
{
get { return _AssignedToUserId; }
set
{
_AssignedToUserId = value;
base.AssignedTo = userManager.Get(_AssignedToUserId);
}
}
private int _SourceUserId;
public int SourceUserId
{
get { return _SourceUserId; }
set
{
this._SourceUserId = value;
base.Source = userManager.Get(_SourceUserId);
}
}
public IntermediateTask() : base("", "", new IntermediateUser(), new IntermediateUser())
{
}
}
public class Task
{
public Task(string title, string description, User assignedTo, User source, DateTime? dateCreated = null, int id = 0)
{
this.RelatedTasks = new List<Task>();
this.Title = title;
this.Description = description;
this.AssignedTo = assignedTo;
this.Source = source;
this.DateCreated = dateCreated ?? DateTime.Now;
this.Id = id;
}
private int _Id;
public int Id
{
get { return _Id; }
protected set { _Id = value; }
}
public string Title { get; set; }
public string Description { get; set; }
public User AssignedTo { get; set; }
public User Source { get; set; }
public DateTime DateCreated { get; set; }
public DateTime? DateAssigned { get; set; }
public DateTime? DateCompleted { get; set; }
public IList<Task> RelatedTasks { get; set; }
public string Notes { get; set; }
override public string ToString()
{
return $"Id: {Id}; Title: {Title}";
}
}
In my case it complained about AssignedTo missing, but that is actually a property in the class that is not in the csv, so I had to add these two lines to make it work:
csv.Configuration.HeaderValidated = null;
csv.Configuration.MissingFieldFound = null;
I don't know why it would come up with 'Name' unless you have something different.

Best way to write application data to a file in WPF

I am using the Caliburn.Micro MVVM pattern.
I am writing an application that has 2 DataGrids, one holds a BindableCollection of RepairOrder, the other a BindableCollection WriteOff.
BindableCollection_WriteOff is property of BindableCollection_RepairOrder. (See the below code).
I need to find a way to write all the RepairOrder including the WriteOff associated with each RO. Besides RepairOrder class holding the WriteOff class, the WriteOff class does not have a way to tie the WriteOff to a RepairOrder.
Repair Order Class:
public class RepairOrder
{
public string Schedule { get; set; }
public string ControlNumber { get; set; }
public int Age { get; set; }
public double Value { get; set; }
public string Note { get; set; }
public double OrgValue { get; set; }
private List<WriteOff> _myWriteOffs;
public List<WriteOff> GetMyWriteOffs()
{
return _myWriteOffs;
}
public void AddMyWriteOff(WriteOff value)
{ _myWriteOffs.Add(value); }
public void DeleteMyWriteOff(WriteOff value)
{ _myWriteOffs.Remove(value); }
public RepairOrder(string CN, string SC, double VL)
{
ControlNumber = CN;
Schedule = SC;
Value = Math.Round(VL, 2);
Note = null;
_myWriteOffs = new List<WriteOff>();
}
public RepairOrder()
{
_myWriteOffs = new List<WriteOff>();
}
public static RepairOrder FromCSV(string CSVLine, string Sched)
{
string[] values = CSVLine.Split(',');
RepairOrder rep = new RepairOrder();
rep.ControlNumber = values[2];
rep.Value = Math.Round(double.Parse(values[5]),2);
rep.Age = int.Parse(values[4]);
rep.Schedule = Sched;
return rep;
}
}
Write Off Class:
public class WriteOff
{
private string _store;
public string Account { get; set; }
public string Description { get; set; }
public double WriteOffAmount { get; set; }
public string Schedule { get; set; }
public string Store
{
get {
if (String.IsNullOrEmpty(_store)) return "";
string temp = _store.Substring(0, 3);
return temp;
}
set { _store = value; }
}
public string Note { get; set; }
public WriteOff(string Acct, string Desc, double Amount, string _store)
{
Account = Acct;
Description = Desc;
WriteOffAmount = Amount;
Store = _store;
}
public string GetWOAccount() {
string SchedAccountNumber = "";
//{ "Navistar", "Cummins", "Misc", "Kenworth", "Mack/Volvo" }
switch (Account)
{
case "Navistar":
SchedAccountNumber = "222000";
break;
case "Cummins":
SchedAccountNumber = "223000";
break;
case "Misc":
SchedAccountNumber = "224500";
break;
default:
SchedAccountNumber = "";
break;
}
return SchedAccountNumber;
}
}

set is throwing StackOverflowException C#

I am trying to get and send a list of this object to a text file. The text file is in the following format.
name,IDnumber,department,value
there are quite a few lines of this so i used a for to read them in.
This is the code for the read and write to the file.
public List<Employee> ReadFile(string fileName) {
StreamReader fileIn = new StreamReader(fileName);
fileIn = File.OpenText(fileName);
List<Employee> list = new List<Employee>();
string[] test;
string name;
string ID;
string dep;
string post;
while (!fileIn.EndOfStream || !File.Exists(fileName)) {
string inString = fileIn.ReadLine();
test = inString.Split('#');
name = test[0];
ID = test[1];
dep = test[2];
post = test[3];
Employee newEmp = new Employee(name, ID, dep, post);
list.Add(newEmp);
}
fileIn.Close();
return list;
}
public void WriteFile(List<Employee> outList, string file) {
StreamWriter writeOut = new StreamWriter(file);
for (int i = 0; i < outList.Count; i++) {
writeOut.WriteLine(outList[i].name + '#' + outList[i].IDnum + '#' + outList[i].department + '#' + outList[i].position);
}
writeOut.close();
}
This is the code for my class. The error is being thrown at the set.
public class Employee {
public string name { get { return name; } set { name = value; } }
public string IDnum { get { return IDnum; } set { IDnum = value; } }
public string department { get { return department; } set { department = value; } }
public string position { get { return position; } set { position = value; } }
public Employee() {
name = string.Empty;
IDnum = string.Empty;
department = string.Empty;
position = string.Empty;
}
public Employee(string newName, string newID) {
name = newName;
IDnum = newID;
department = string.Empty;
position = string.Empty;
}
public Employee(string newName, string newID, string newDep, string
newPost) {
name = newName;
IDnum = newID;
department = newPost;
position = newDep;
}
}
I am not sure if there is some kind of formatting that I am missing for the set function to function as needed. The This is the function i am calling for the in and out of the file. I believe that it is never making it to the out so it is likely how i am importing the data.
It's a really common gotcha... a C# rite of passage!
Let's take a look at a single property (this applies to all of your properties though)...
public string name { get { return name; } set { name = value; } }
so what happens when you try myObj.name = "foo";?
In the set method, you refer back to the very same property name. So it tries to access name, which goes around again (and again, and again, recursively until you StackOverflow).
A backing field with proper naming conventions is the norm here:
private string name;
public string Name{get { return name; } set{ name = value; }}
or even better, if there's no logic involved, an auto-property.
public string Name{ get; set; }
You keep calling IDnum and other properties over and over recursively, until the stack overflows
public string IDnum { get { return IDnum; } set { IDnum = value; } }
When you do something like
IDnum = someValue;
that calls the setter for IDnum, which runs the code in the setter
IDnum = value
Which in turn calls the setter of IDnum, until you run out of stack.
The Fix
In your case, it looks like you can use automatic properties
public string IDnum { get; set; }
You should change
public string name { get { return name; } set { name = value; } }
public string IDnum { get { return IDnum; } set { IDnum = value; } }
public string department { get { return department; } set { department = value; } }
public string position { get { return position; } set { position = value; } }
to
public string name { get; set; }
public string IDnum { get; set; }
public string department { get; set; }
public string position { get; set; }
or introduce backing fields:
private string _name;
public string name { get { return _name; } set { _name = value; } }
See https://msdn.microsoft.com/en-us/library/bb384054.aspx for more info on Auto-Implemented Properties in C#.
Please note, that the commonly used naming of public properties is PascalCasing. Your properties in PascalCasing would look like this:
public string Name { get; set; }
public string IdNum { get; set; }
public string Department { get; set; }
public string Position { get; set; }

VS 2008 complains about a property code not generated because the subjacent type is not marked Seializable

Annoying error (first time I see it) "Code generation for property 'SourceFieldList' failed. Error was: Type 'KeyboardEnabledControls.SortFieldDescriptor' in Assembly ... is not marked as serializable."
The code for that property follows
protected List<SortFieldDescriptor> sourceFieldsList;
public List<SortFieldDescriptor> SourceFieldList
{
get
{
if (DesignMode) {
sourceFieldsList = new List<SortFieldDescriptor>();
}
return sourceFieldsList;
}
set
{
if (DesignMode)
return;
sourceFieldsList = value;
}
}
The class (it's a user control) has another property tailored as much as the one rejected, which don't causes trouble
protected List<SortFieldDescriptor> destinationFieldsList;
public List<SortFieldDescriptor> DestinationFieldList
{
get
{
if (DesignMode) {
destinationFieldsList = new List<SortFieldDescriptor>();
return destinationFieldsList;
}
destinationFieldsList.Clear();
for (int i = 0; i < destinationList.Items.Count; i++) {
SortFieldDescriptor sd = (SortFieldDescriptor)destinationList.Items[i];
sd.EnableControlBreak = destinationList.GetItemChecked( i );
}
return destinationFieldsList;
}
set
{
if (DesignMode)
return;
destinationFieldsList = value;
}
}
Finally, the "culprit" class
[Serializable()]
public class SortFieldDescriptor
{
public string Abrev { get; protected set; }
public string FullName { get; protected set; } // the logical name of field
public string ComboDisplay { get { return String.Format( "{0} ({1})", FullName, Abrev ); } }
public string PropertyName { get; protected set; }
public bool EnableControlBreak { get; set; }
public SortFieldDescriptor( string abr, string fname, string pname )
{
Abrev = abr;
FullName = fname;
PropertyName = pname;
}
public override string ToString()
{
return ComboDisplay;
}
}
aS YOU can see, I marked the type as Serializable() (even if I dont want to serialize it) at no avail: the error persists.
TIA

entity framework saves first item in the loop but none other

In my controller I'm looping through items and saving them to my db. The problem is that it saves the first item, but none of the others. I put a breakpoint on the "SaveItem()" line in the loop and it hits it every time, but what seems odd to me is that it only goes through to the method for the 1st item.
What am I doing wrong?
public void SubmitItem(Cart cart, ShippingDetails shippingDetails, ProcessedItems processedItem, string orderID)
{
var cartItems = cart.Lines;
//CartIndexViewModel cartIndex = new CartIndexViewModel();
//var customID = cartIndex.OrderID;
foreach(var item in cartItems)
{
processedItem.OrderID = orderID;
processedItem.ProductID = item.Product.ProductID;
processedItem.Name = item.Product.Name;
processedItem.Description = item.Product.Description;
processedItem.Price = item.Product.Price;
processedItem.Category = item.Product.Category;
processedItem.ImageName = item.Product.ImageName;
processedItem.Image2Name = item.Product.Image2Name;
processedItem.Image3Name = item.Product.Image3Name;
processedItem.BuyerName = shippingDetails.Name;
processedItem.Line1 = shippingDetails.Line1;
processedItem.Line2 = shippingDetails.Line2;
processedItem.Line3 = shippingDetails.Line3;
processedItem.City = shippingDetails.City;
processedItem.State = shippingDetails.State;
processedItem.Zip = shippingDetails.Zip;
processedItem.Country = shippingDetails.Country;
processedItem.Status = "Submitted";
processedItems.SaveItem(processedItem);
}
}
public class EFProcessedItemsRepository : IProcessedItems
{
private EFDbContext context = new EFDbContext();
public IQueryable<ProcessedItems> ProcessedItem
{
get { return context.ProcessedItems; }
}
public void SaveItem(ProcessedItems processedItem)
{
if(processedItem.ProcessedID == 0)
{
try
{
context.ProcessedItems.Add(processedItem);
context.SaveChanges();
}
catch (Exception)
{
throw;
}
}
else
{
context.Entry(processedItem).State = EntityState.Modified;
}
}
public void DeleteItem(ProcessedItems processedItem)
{
context.ProcessedItems.Remove(processedItem);
context.SaveChanges();
}
}
here is the class for the processedItem:
public class ProcessedItems
{
[Key]
public int ProcessedID { get; set; }
public string OrderID { get; set; }
public int ProductID { get; set; }
public string Name { get; set; }
public string Description { get; set; }
public decimal Price { get; set; }
public string Category { get; set; }
public string ImageName { get; set; }
public string Image2Name { get; set; }
public string Image3Name { get; set; }
public string Status { get; set; }
//shipping
public string BuyerName { get; set; }
public string Line1 { get; set; }
public string Line2 { get; set; }
public string Line3 { get; set; }
public string City { get; set; }
public string State { get; set; }
public string Zip { get; set; }
public string Country { get; set; }
}
Interface:
public interface IProcessedItems
{
IQueryable<ProcessedItems> ProcessedItem { get; }
void SaveItem(ProcessedItems processedItem);
void DeleteItem(ProcessedItems processedItem);
}
try calling context.SaveChanges() after adding all of the items, I think it should persist them all in one go.
Another thing to try:
Refactor your code so that SaveItem accepts only one item to save, Add it and call SaveChanges()
Loop through the cart items outside the method and call the method with one item to save at a time.
// set orderID, shippingDetails above
foreach(var item in cartItems)
{
ProcessedItems processedItem = new ProcessedItems();
processedItem.OrderID = orderID;
processedItem.ProductID = item.Product.ProductID;
processedItem.Name = item.Product.Name;
processedItem.Description = item.Product.Description;
processedItem.Price = item.Product.Price;
processedItem.Category = item.Product.Category;
processedItem.ImageName = item.Product.ImageName;
processedItem.Image2Name = item.Product.Image2Name;
processedItem.Image3Name = item.Product.Image3Name;
processedItem.BuyerName = shippingDetails.Name;
processedItem.Line1 = shippingDetails.Line1;
processedItem.Line2 = shippingDetails.Line2;
processedItem.Line3 = shippingDetails.Line3;
processedItem.City = shippingDetails.City;
processedItem.State = shippingDetails.State;
processedItem.Zip = shippingDetails.Zip;
processedItem.Country = shippingDetails.Country;
SubmitItem(processedItem);
}
public void SubmitItem(ProcessedItems processedItem)
{
processedItem.Status = "Submitted";
processedItems.SaveItem(processedItem);
}
I think it is because processedItem is the same instance for each loop iteration. So after it has been through SaveItem once, it has its ProcessedID set and therefore won't get processed again.
My first guess is that you always store one entity, which is stored in processedItem, which is a input parameter. Try to create new Entity on each loop and then save it. In other words, you assign values to input parameter
processedItem.OrderID = orderID;
and then store same entity each time, but with changed fields
processedItems.SaveItem(processedItem);

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