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Null reference error "Object reference not set to an instance of an object" accessing Model while loading a view
You need to initialize the Model I suppose, just like we do in C#: Suppose we have a class, then we initialize the same like: Model m1= new Model(); Make sure you check the null also for all items you are passing.

Categories : Asp Net Mvc

C# - Null reference exception was unhandled - object reference not set to an instance of an object
When your Insert method hits a leaf, currentNode.left or currentNode.right will be null. At this point, you're not checking for null, so you'll receive this exception on that line as you try to access the color. You need to add null checks on insert to handle the leaf condition.

Categories : C#

Object reference not set to an instance of an object - Null Reference Exception
You have to check this value before access it. For example, like this: var form = System.Web.HttpContext.Current.Request.Form; if (form != null && !String.IsNullOrEmpty(day) && form.AllKeys.Contains(day)) { var test = form[day].ToString(); }

Categories : C#

How can find wich object cause null object reference in Flash?
Run the code from Flash Builder (with your source hooked up in some sort of Project--which kind will depend on what you have). The debugger should stop at the line with the error, and you can see which variable is null.

Categories : Actionscript

"Object reference not set to an instance of an object" even when I checked null
You can try to use count too, like this: IEnumerable<Room> room=... if (room == null) // Check for nulls return null; else if (room.count() == 0) // Check if empty return null; else if(!room.Any(x => x.Beds == null) // Check if there is no null Beds return room.SelectMany(r=>r.Beds);

Categories : C#

Why would an event be null? (object reference not set to an instance of an object)
The event is null, if noone subscribed to it yet. So it's a good practice to control on null equality, like: public void usbforProcessExited(object sender, EventArgs f) { if(SetStatusEvent!=null) SetStatusEvent(100, "DONE", Color.Green); } That's why outside it works well, as you have, this line: rsSet.SetStatusEvent += new RemoteS.SetStatus(updateStatus); so subscription and initilizaton of the event. When you call it from inside, there is no any subscription made, so event is null. EDIT Following the comments let's provide more thread safe approach of handling null reference check on event: public void usbforProcessExited(object sender, EventArgs f) { var ev = SetStatusEvent; //[1] if(ev!=null) //[2] ev(10

Categories : C#

Object reference not set to an instance of an object in c# how to check for null value?
Try this if(data != null) { } Or if(object.ReferenceEquals(data,null)) { } Probably as @zigdawgydawg pointed out exception will not be in checking data because string.Split will never return null. So, you need to avoid null parameter. if(info==null || info.details == null) { return null;//Or throw new ArgumentException(); }

Categories : C#

Session Variable List, when adding a new Object I get Object reference not set to an instance of an object
After Session["SessionStats"] = new UserSession(); you have added a new UserSession, whose Option property is null, to Session. Then, when you do ((UserSession)Session["SessionStats"]).Options.Add(RO); you are pulling out that very same object and accessing the Option property, which is null, hence the NullReferenceException. It looks like you are forgetting to assign something to the newly created UserOption's Option property. However, you don't seem to be using the Options you are instantiating in the foreach for anything...

Categories : Asp Net

AS3 null-object reference
I read your code, the only potentially issue is sound variable, can be null. Have you instantiated sound variable? If sound is valued, the method play (of variable sound) can return a null value? EDIT AFTER COMMENTS: Hi, view this and this issue

Categories : Actionscript

Partial View with Different Models, Null Reference Error
Good afternoon, it looks like in your get request for the Register view you are more than likely not directly instantiating your RegisterModel so when you pass Model.Login to your partial call it is null.

Categories : Asp Net Mvc

Reading values into a List object - Object reference not set to an instance of an object
This change should solve the problem: MyVec::MyVec(void) { MyVector = gcnew List<double>(); } Class member MyVector is initailly null reference. You need to initialize it before using, and MyVec constructor is appropriate place to do it.

Categories : List

Object reference not set to an instance of an object. : grid view inside repeater
Check your gd object weather it is null or not than execute your certain conditions. Thus the code should be like below: GridView gd = (GridView)e.Item.FindControl("gvDetails"); if(gd != null) { gd.DataSource = employees; gd.DataBind(); } Edit: The error is coming because the name in the DataField="ItemDescription" of asp:BoundField doesn't match the datasource employees properties which you have specified at the time of databind. The markup code should be <asp:BoundField DataField="itemdesc" HeaderText="Item Description"/>

Categories : Asp Net

Null Object Reference Exception
When you try to add, at that point selectedGroup.Students property is null. Do this if (selectedGroup.Students == null) selectedGroup.Students = new List<Student>(); // If its a List selectedGroup.Students.Add(studentToAdd);

Categories : C#

Object reference not set to an instance while not being null
It's possible that one of the Thing's in subset is null. You can try this: IEnumerable<Thing> subset = things.Where(a => a != null && a.SomeFlag); Note that due to the way Linq's lazy evaluation, you won't get any exception you call .Where because all it's doing at that point is setting up a condition for filtering the elements of things. Only later when you call .Count is it actually evaluating the results. Update: With the new null-condition operator in C# 6 (also called the safe navigation or 'Elvis' operator), we can do the same thing a bit more succinctly: IEnumerable<Thing> subset = things.Where(a => a?.SomeFlag);

Categories : C#

Adding to a List causing null reference
Valid is null, you have to initialize it: public class UploadResult { public List<CSVModel> InvalidField = new List<CSVModel>(); public List<CSVModel> Valid = new List<CSVModel>(); } or via constructor: public class UploadResult { public UploadResult() { InvalidField = new List<CSVModel>(); Valid = new List<CSVModel>(); } public List<CSVModel> InvalidField; public List<CSVModel> Valid; }

Categories : C#

Object reference not set to an instance of an object when creating observable collection from list
In this code, either db or Tables is null. var list = db.Tables.ToList(); Make sure to check that before: if (db != null && ds.Tables != null) { var list = db.Tables.ToList(); }

Categories : C#

Object reference not set to an instance of an object when attempting to assign array from list
You never initialize rootAndKey before trying to assign elements to it. Your looping logic also looks a little funny to me. I'm guessing you'll need something like: string[][] rootAndKey = new string[allRoots.Count][]; for(var i = 0; i < allRoots.Count; i++) { var subkeys = root.GetSubKeyNames(); rootAndKey[i] = new string[subkeys.Length]; for(var h = 0; h < subkeys.Length; h++) { rootAndKey[i][h] = subkeys[h]; } }

Categories : C#

object reference not set to an instance of object exception when I try to add element to an array of type List
You haven't created any lists. When you create an array of lists, it won't automatically create all the lists in the array, you have to do that manually: List<string>[] Toursist = new List<string>[numtoursut]; for (int i = 0; i < Toursist.Length; i++) { Toursist[i] = new List<string>(); }

Categories : Asp Net

Data List Header Template causing 'Object reference not set to an instance of an object' error
It's difficult to diagnose this without seeing your code, but I would guess that your DataList1_ItemDataBound method is trying to find the lblExp control in the e.Item without checking the e.Item.ItemType first. This event will be raised for every item in the list, including the header, and the header doesn't contain a control called lblExp. You need to check the ItemType before processing the item: protected void DataList1_ItemDataBound(object sender, DataListItemEventArgs e) { switch (e.Item.ItemType) { case ListItemType.Item: case ListItemType.AlternatingItem: case ListItemType.SelectedItem: case ListItemType.EditItem: { Label lblExp = (Label)e.Item.FindControl("lblExp"); ... } } }

Categories : C#

Error : Object null reference when trying to get a control from Form.Controls collection
As I said in my comment you can't use a control's name as the indexer of Controls collection to get it but you can iterate through the controls collection find the desired control and do whatever you want with it, try this: Label lbl = null; foreach (var control in this.ParentForm.Controls) { if (((Control)control).Name == "lblMenuItem") { lbl = (Label)control; break; } } if (lbl != null) lbl.Text = "Medical College List"; or if you want to write less code : Control[] foundControls = this.Controls.Find("lblMenuItem", true); if (foundControls.Any()) foundControls.First().Text = "Medical College List";

Categories : C#

What does List.Add(List[index]) creates a new object or a reference?
So this is what I ended up doing... Kindly suggest a better method if you know one. for (int k = 0; k < (count); k++) { myList.Add((string[][])myList[k].Clone()); } Is there any other way to do this? Without having to iterate through every list member?

Categories : C#

Using stage.addEventListener inside a class is returning a null object reference during runtime
Wait for the ADDED_TO_STAGE event to fire first: public function ChoiceButton():void { // your code.. etc.. addEventListener(Event.ADDED_TO_STAGE,addListeners); } private function addListeners(event:Event):void { stage.addEventListener(AnswerEvent.EVENT_ANSWERED, update); }

Categories : Actionscript

AS3: TypeError: Error #1009: Cannot access a property or method of a null object reference. Help Needed
At least one of this variables are null when pickup() function executes: guy key coin1 scorebox coin2 coin3 coin4 You can use trace() function to check which one. function pickup() { trace('guy==' + guy); trace('key==' + key); trace('scorebox==' + scorebox); trace('coin1==' + coin1); trace('coin2==' + coin2); trace('coin3==' + coin3); trace('coin4==' + coin4); if (guy.hitTestObject(key)) { key.visible = false; } if (guy.hitTestObject(coin1)) { coin1.x = 2000; score++; scorebox.text = score.toString(); } if (guy.hitTestObject(coin2)) { coin2.x = 2000; score++; scorebox.text = score.toString(); } if (guy.hitTestObject(coin3)) { coin3.x = 2000;

Categories : Actionscript

Error #1009: null object reference - When adding a DataGrid to a ActionScript Mobile project
Try if possible rebuilding in CS6. I'm trying to resolve a similar random error 'Error #1009: Cannot access a property or method of a null object reference' and I can only surmise that CC is the culprit. If rebuilding in CS6 solves your problem, please let me know!

Categories : Actionscript

Binding to DataGridView Datasource property with List(Of Entity) throw a null reference exception
For those beginner who will also encounter this problem what I did on my FinalClassScoreModel class public class FinalClassScoreModel { private readonly FinalClassScore _finalClassScore; private readonly Enroll _enroll; public FinalClassScoreModel(FinalClassScore finalClassScore, Enroll enroll) { this._finalClassScore = finalClassScore; this._enroll = enroll; } public int EnrollId { get { return this._finalClassScore.EnrollId; } } public string StudentNo { get { return this._enroll.StudentNo; } } on this way it will just get the value ot StudentNo even if it is null or not thanks to all

Categories : C#

TypeError: Error #1009: Cannot access a property or method of a null object reference. Can't Use stage.addEventListener
You cannot access the stage because it is being called before the object is actually added to the stage. This usually happens when you try to access the stage in constructors. Use the AddedToStage Event instead. Try this: public function MenuMain(){ addEventListener(Event.ADDED_TO_STAGE, onAddedToStage); } public function onAddedToStage(e:Event):void{ stage.addEventListener(KeyboardEvent.KEY_DOWN, keyDownHandler); stage.addEventListener(KeyboardEvent.KEY_UP, keyUpHandler); stage.addEventListener(Event.ENTER_FRAME, loop); removeEventListener(Event.ADDED_TO_STAGE, onAddedToStage); }

Categories : Actionscript

TypeError: Error #1009: Cannot access a property or method of a null object reference at pizzaBaking/doRESTART()
1: Turn on Debugging Go to your publish settings and enable "Permit Debugging". This will take your ambiguous error... null object reference at pizzaBaking/doRESTART() ...to a much clearer... null object reference at pizzaBaking/doRESTART() scriptpizzaBaking.as:35 ...which now denotes which line in your code to look for your issue. 2: Use the Debug Console Use the debugging compile mode to bring up the Debug Console. This will provide you with an immediate look at the line of code in question, as well as the Call Stack, and the state of all available Variables. No programmer should be without one. 3: parent == null When doRESTART() is being called, it no longer has a parent, ergo, when you call MovieClip(parent) it returns a null, and there is no MENUS property on null.

Categories : Actionscript

TypeError: Error #1009: Cannot access a property or method of a null object reference. at _010_fla::MainTimeline/frame31()
I guess you are writing code on frames rather than different class file. In frame case sometimes the object or method are not ready to be used when you switch frames from gotoAndStop() or gotoAndPlay(); My suggestion is add .1sec delay(Timer Event) before using anyFunction or using any property or anyThing... and when the timer gives you callback ... do whatever you want. Try this worth a shot... This will definately solve your problem if i am understanding it correctly.

Categories : Actionscript

TypeError: Error #1009: Cannot access a property or method of a null object reference. at RECOVER_fyp1_fla::MainTimeline/abc1()
but these variables: mosq1.y = mosq1.y + 2; mosq2.y = mosq2.y + 3; mosq3.y = mosq3.y + 4; mosq4.y = mosq4.y + 5; mosq5.y = mosq5.y + 6; are instantiated?? Peraphs these are null. Error code is clear, you're trying to use a property of a NULL object

Categories : Actionscript

Using customlistviews in android : Keep on getting list view = NULL
Every time you want to add an object to a list, you have to provide a view for the object. Android asks your list adapter, be it custom or system-defined, it asks the adapter what each list item is supposed to look like. This is where getView() comes into play. public abstract View getView (int position, View convertView, ViewGroup parent): Get a View that displays the data at the specified position in the data set. If convertView is null, you will get an NPE. Tutorials here: http://www.javacodegeeks.com/2013/06/android-listview-tutorial-and-basic-example.html

Categories : Android

Django REST framework: Can a nested object access its parent object's details in a List View?
Moment of clarity: the solution is to use a SerializerMethodField to instantiate the RepSummarySerializer and pass the customer_id in the context: class CustomerSummarySerializer(serializers.HyperlinkedModelSerializer): id = ... name = ... rep = serializers.SerializerMethodField('get_rep') def get_rep(self, obj): rep = obj.rep serializer_context = {'request': self.context.get('request'), 'customer_id': obj.id} serializer = RepSummarySerializer(rep, context=serializer_context) return serializer.data The customer_id can now be accessed in RepSummarySerializer.get_rep_url like this: def get_rep_url(self, obj): customer_id = self.context.get('customer_id') ... Don't know why I didn't think of this thr

Categories : Django

The partial view to display a list I think I said that the parameters are null when it is not
In the view where I call the partial the sintax of call is: @Html.Action("Metodo") where Metodo is a method in my control class My error was that y write: @Html.Partial("source.ext")

Categories : Asp Net Mvc

How to manage two list object reference that are pointing to same collection?
It's hard to tell what you're asking, but if you're trying to keep a copy of the original list you will need to make a copy instead of assigning the reference. frmPrepare.lstBtn = Program.currOrder.OrderItems[currIdx].AppliedCustomization; frmPrepare.actualBtnLIst = frmPrepare.lstBtn.ToList(); // ToList will create a copy of each item reference in the collection.

Categories : C#

Object reference error adding a new select list item
Probably You didn't initialized VideoList in the parameterless constructor of HammerpointVideoListModel class, so it is NOT an empty list. Put VideoList = new List<SelectedListItem>(); in the constructor.

Categories : C#

Android Fragment: View fully from code causes binding to null-object
SOLVED Sigh. Not the first time this happens a few minutes after finally asking it here after hours of frustration.. Solved it (at least it is working now): BindingContext = new MvxAndroidBindingContext (Activity, new MvxSimpleLayoutInflater(inflater), ViewModel); In my code the last parameter was not provided. So probably the binding context was not fully set. In MvvmCross code I found some warning that EnsureBindingContext was not working... Now testing if the delaybind is working again...

Categories : Android

getting error TypeError: Error #1009: Cannot access a property or method of a null object reference
That means that navBtn4 doesn't have the "addEventListener" method at the time when you're running that code. Try using the debugger with a break point on that line and checking that whether or not it has been initialised.

Categories : Actionscript

Getting NULL Pointer Exception while updating a Custom List View in Main Activity
try this using public class CustomListViewAdapter extends BaseAdapter { private List<RowItem> arr = new ArrayList<RowItem>(); private Context context; public CustomListViewAdapter(Context context,List<RowItem> items) { this.arr = items; this.context=context; } @Override public int getCount() { // TODO Auto-generated method stub return arr.size(); } @Override public Object getItem(int arg0) { // TODO Auto-generated method stub return arr.get(arg0); } @Override public long getItemId(int arg0) { // TODO Auto-generated method stub return 0; } class ViewHolder { TextV

Categories : Android

Making a DOM element reference change to a null reference when removed from the DOM
You can't, because you store in a variable, just call var a = document.getElementById('a') when you need check. var a = document.getElementById('a'); alert(a); // Alerts "[object HTMLDivElement]". a.parentNode.removeChild(a); a = document.getElementById('a'); alert(a); // "undefined".

Categories : Javascript

How could this reference to a string be causing a Null Reference Exception?
if PendingCommands.SiteFetchSiteNumber is null (and thus sNum is null), then this would cause a null reference exception when you call sNum.Trim() Also if you show the full stack trace it should give you the exact line number that the error occurred on, which is a lot simpler to debug than using an incremental value to figure it out.

Categories : C#

Why is CodeContract warning about a null reference, when the ObjectInvariant checks it for null
I think invariant only runs on public property access. Is it possible to add a contract to the RowDefinitions property itself? Your invariant can't prove that property won't be null; you could call a method on that type which sets it to null after your invariant runs.

Categories : C#



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