I have problem with windows phone 8 local database. That's how my database code looks:
[Table(Name = "Folders")]
public class FolderTable : INotifyPropertyChanged, INotifyPropertyChanging, IEqualityComparer<FolderTable>
{
private string _folderName;
private string _description;
private string _password;
private string _tileColorName;
[Column(IsPrimaryKey = true)]
public string FolderName
{
get { return _folderName; }
set
{
if (_folderName != value)
{
NotifyPropertyChanging();
_folderName = value;
NotifyPropertyChanged();
}
}
}
[Column(CanBeNull = false)]
public string Description
{
get { return _description; }
set
{
if (_description != value)
{
NotifyPropertyChanging();
_description = value;
NotifyPropertyChanged();
}
}
}
[Column]
public string Password
{
get { return _password; }
set
{
if (_password != value)
{
NotifyPropertyChanging();
_password = value;
NotifyPropertyChanged();
}
}
}
[Column]
public string TileColorName
{
get { return _tileColorName; }
set
{
if (_tileColorName != value)
{
NotifyPropertyChanging();
_tileColorName = value;
NotifyPropertyChanged();
}
}
}
private void NotifyPropertyChanging([CallerMemberName] string propertyName = "")
{
if ( PropertyChanging != null)
PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
}
private void NotifyPropertyChanged([CallerMemberName] string propertyName = "")
{
if ( PropertyChanged != null )
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
public event PropertyChangedEventHandler PropertyChanged;
public event PropertyChangingEventHandler PropertyChanging;
public bool Equals(FolderTable x, FolderTable y)
{
return x.FolderName == y.FolderName;
}
public int GetHashCode(FolderTable obj)
{
return obj.FolderName.GetHashCode();
}
}
Folder add:
public Task Add(Folder folder)
{
var folderTable = GetFolderTable(folder);
_databaseContext.Folders.InsertOnSubmit(folderTable);
return Task.FromResult(true);
}
Commit:
public Task Commit()
{
try
{
_databaseContext.Folders.Context.SubmitChanges();
}
catch (DuplicateKeyException duplicateKeyException)
{
_databaseContext.Dispose();
_databaseContext = new FolderDbContext(FolderDbContext.DBConnectionString);
throw new FolderAlreadyExistsException(duplicateKeyException);
}
return Task.FromResult(true);
}
When I Add new Folder (folder with such name didn't exist before), Commit and then I try add folder with same name DuplicateKeyException is thrown and handled correctly. However after context gets recreated in catch section the next call to Add and Commit folder with same name throws SqlCeException with message: "A duplicate value cannot be inserted into a unique index. [ Table name = Folders,Constraint name = PK_Folders ]". Is that normal behaviour or am I doing something wrong? In what cases DuplicateKeyException is thrown? How to catch SqlCeException? I can't even see System.Data.SqlServerCe namespace.
use reflection to get the type name of the ex eption, if you wish to catch the SqlCeException explicitly:
ex.GetType().Name == "SqlCeException"
Related
I am right now using a nested ObservableCollection to fill in the rows of a DataGrid with the inner ObservableCollection holding information regarding each cell as follows:
public class MemoryTable : INotifyPropertyChanged
{
string _Address;
public string Address
{
get
{
return _Address;
}
set
{
if (_Address != value)
{
_Address = value;
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
void RaisePropertyChanged(string prop)
{
if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(prop)); }
}
bool _NextRowOverflow;
public bool NextRowOverflow
{
get
{
return _NextRowOverflow;
}
set
{
if (_NextRowOverflow != value)
{
_NextRowOverflow = value;
}
}
}
private ObservableCollection<DataAssets> _DataSpace;
public ObservableCollection<DataAssets> DataSpace
{
get
{
return _DataSpace;
}
set
{
_DataSpace = value;
RaisePropertyChanged("DataSpace");
}
}
public MemoryTable()
{
DataSpace = new ObservableCollection<DataAssets>();
}
public class DataAssets : INotifyPropertyChanged
{
string _Addresses;
public string Addresses
{
get
{
return _Addresses;
}
set
{
if (_Addresses != value)
{
_Addresses = value;
RaisePropertyChanged("Addresses");
}
}
}
string _Values;
public string Values
{
get
{
return _Values;
}
set
{
if (_Values != value)
{
_Values = value;
RaisePropertyChanged("Values");
}
}
}
string _ToolTip;
public string ToolTip
{
get
{
return _ToolTip;
}
set
{
if (_ToolTip != value)
{
_ToolTip = value;
RaisePropertyChanged("ToolTip");
}
}
}
Brush _Color;
public Brush Color
{
get
{
return _Color;
}
set
{
if (_Color != value)
{
_Color = value;
RaisePropertyChanged("Color");
}
}
}
string _ConvertedValue;
public string ConvertedValue
{
get
{
return _ConvertedValue;
}
set
{
if (_ConvertedValue != value)
{
_ConvertedValue = value;
RaisePropertyChanged("ConvertedValue");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
void RaisePropertyChanged(string prop)
{
if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(prop)); }
}
}
}
}
And want it to update whenever I change one of the values in the DataAsset class, however whenever I change a value by such a means:
NextRow.DataSpace[i].Color = Brushes.Yellow;
None of the cells update, the workaround i made for doing this is to clear and rewrite the entire ObservableCollection like this:
ObservableCollection<MemoryTable> Temp = new ObservableCollection<MemoryTable>();
foreach (var item in MemoryTable)
{
if (Temp.IndexOf(item) < 0)
{
Temp.Add(item);
}
}
MemoryTableDisplay.Clear();
foreach (var item in Temp)
{
if (MemoryTableDisplay.IndexOf(item) < 0)
{
MemoryTableDisplay.Add(item);
}
}
By this method I am able to force the UI to display the changes, however when moving further to working on a larger set of data, this method takes too long to accomplish, is it possible to have the inner properties to cause an update for the entire ObservableCollection?
Thank you!
Please try this.
NextRow.DataSpace[i].Color = Brushes.Yellow;
After writing down one more statement like this.
NextRow.DataSpace= NextRow.DataSpace;
I have a set of classes that I am using to deserialize JSON into. My program will periodically look for changes to this JSON file, and if it finds any, will push the new data to the properties of these classes using reflection.
I need to find any new items added to the collection of the Item2 class (SocialExportJSON.SocialExportData.Item2) after a successful update.
My JSON classes look like this (there are more but I want to avoid too big a wall of code):
public class Item2 : INotifyPropertyChanged
{
[JsonProperty("type")]
private string type;
public string Type
{
get
{
return type;
}
set
{
if (type != value)
{
type = value;
RaisePropertyChanged("Type");
}
}
}
[JsonProperty("id")]
private string id;
public string ID
{
get
{
return id;
}
set
{
if (id != value)
{
id = value;
RaisePropertyChanged("ID");
}
}
}
[JsonProperty("postedIso8601")]
private string postedIso8601;
public string PostedIso8601
{
get
{
return postedIso8601;
}
set
{
if (postedIso8601 != value)
{
postedIso8601 = value;
RaisePropertyChanged("PostedIso8601");
}
}
}
[JsonProperty("postedTimestamp")]
private object postedTimestamp;
public object PostedTimestamp
{
get
{
return postedTimestamp;
}
set
{
if (postedTimestamp != value)
{
postedTimestamp = value;
RaisePropertyChanged("PostedTimestamp");
}
}
}
[JsonProperty("engagement")]
private Engagement engagement;
public Engagement Engagement
{
get
{
return engagement;
}
set
{
if (engagement != value)
{
engagement = value;
RaisePropertyChanged("Engagement");
}
}
}
[JsonProperty("source")]
private Source2 source;
public Source2 Source
{
get
{
return source;
}
set
{
if (source != value)
{
source = value;
RaisePropertyChanged("Source");
}
}
}
[JsonProperty("author")]
private Author author;
public Author Author
{
get
{
return author;
}
set
{
if (author != value)
{
author = value;
RaisePropertyChanged("Author");
}
}
}
[JsonProperty("content")]
private Content content;
public Content Content
{
get
{
return content;
}
set
{
if (content != value)
{
content = value;
RaisePropertyChanged("Content");
}
}
}
[JsonProperty("location")]
private Location location;
public Location Location
{
get
{
return location;
}
set
{
if (location != value)
{
location = value;
RaisePropertyChanged("Location");
}
}
}
[JsonProperty("publication")]
private Publication publication;
public Publication Publication
{
get
{
return publication;
}
set
{
if (publication != value)
{
publication = value;
RaisePropertyChanged("Publication");
}
}
}
[JsonProperty("metadata")]
private Metadata metadata;
public Metadata Metadata
{
get
{
return metadata;
}
set
{
if (metadata != value)
{
metadata = value;
RaisePropertyChanged("Metadata");
}
}
}
//Event handling
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string property)
{
//Console.WriteLine("Updated");
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(property));
}
}
public class SocialExportData : INotifyPropertyChanged
{
[JsonProperty("dataType")]
private string dataType;
public string DataType
{
get
{
return dataType;
}
set
{
if (dataType != value)
{
dataType = value;
RaisePropertyChanged("DataType");
}
}
}
[JsonProperty("id")]
private int id;
public int ID
{
get
{
return id;
}
set
{
if (id != value)
{
id = value;
RaisePropertyChanged("ID");
}
}
}
[JsonProperty("story")]
private Story story;
public Story Story
{
get
{
return story;
}
set
{
if (story != value)
{
story = value;
RaisePropertyChanged("Story");
}
}
}
[JsonProperty("order")]
private string order;
public string Order
{
get
{
return order;
}
set
{
if (order != value)
{
order = value;
RaisePropertyChanged("Order");
}
}
}
[JsonProperty("lifetime")]
private string lifetime;
public string Lifetime
{
get
{
return lifetime;
}
set
{
if (lifetime != value)
{
lifetime = value;
RaisePropertyChanged("Lifetime");
}
}
}
[JsonProperty("maxAge")]
private int maxAge;
public int MaxAge
{
get
{
return maxAge;
}
set
{
if (maxAge != value)
{
maxAge = value;
RaisePropertyChanged("MaxAge");
}
}
}
[JsonProperty("maxSize")]
private int maxSize;
public int MaxSize
{
get
{
return maxSize;
}
set
{
if (maxSize != value)
{
maxSize = value;
RaisePropertyChanged("MaxSize");
}
}
}
[JsonProperty("consumeCount")]
private int consumeCount;
public int ConsumeCount
{
get
{
return consumeCount;
}
set
{
if (consumeCount != value)
{
consumeCount = value;
RaisePropertyChanged("ConsumeCount");
}
}
}
[JsonProperty("consumeInterval")]
private int consumeInterval;
public int ConsumeInterval
{
get
{
return consumeInterval;
}
set
{
if (consumeInterval != value)
{
consumeInterval = value;
RaisePropertyChanged("ConsumeInterval");
}
}
}
[JsonProperty("items")]
private ObservableCollection<Item2> items;
public ObservableCollection<Item2> Items
{
get
{
return items;
}
set
{
if (items != value)
{
items = value;
RaisePropertyChanged("Items");
}
}
}
//Event handling
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string property)
{
//Console.WriteLine("Updated");
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(property));
}
}
public class SocialExportJSON : INotifyPropertyChanged
{
[JsonProperty("id")]
private string id;
public string ID
{
get
{
return id;
}
set
{
if (id != value)
{
id = value;
RaisePropertyChanged("ID");
}
}
}
[JsonProperty("ttl")]
private int ttl;
public int TTL
{
get
{
return ttl;
}
set
{
if (ttl != value)
{
ttl = value;
RaisePropertyChanged("TTL");
}
}
}
[JsonProperty("serial")]
private long serial;
public long Serial
{
get
{
return serial;
}
set
{
if (serial != value)
{
serial = value;
RaisePropertyChanged("Serial");
}
}
}
[JsonProperty("formatType")]
private string formatType;
public string FormatType
{
get
{
return formatType;
}
set
{
if (formatType != value)
{
formatType = value;
RaisePropertyChanged("FormatType");
}
}
}
[JsonProperty("modifiedIso8601")]
private string modifiedIso8601;
public string ModifiedIso8601
{
get
{
return modifiedIso8601;
}
set
{
if (modifiedIso8601 != value)
{
modifiedIso8601 = value;
RaisePropertyChanged("ModifiedIso8601");
}
}
}
[JsonProperty("modifiedTimestamp")]
private long modifiedTimestamp;
public long ModifiedTimestamp
{
get
{
return modifiedTimestamp;
}
set
{
if (modifiedTimestamp != value)
{
modifiedTimestamp = value;
RaisePropertyChanged("ModifiedTimestamp");
}
}
}
[JsonProperty("timezone")]
private string timezone;
public string Timezone
{
get
{
return timezone;
}
set
{
if (timezone != value)
{
timezone = value;
RaisePropertyChanged("Timezone");
}
}
}
[JsonProperty("dataType")]
private string dataType;
public string DataType
{
get
{
return dataType;
}
set
{
if (dataType != value)
{
dataType = value;
RaisePropertyChanged("DataType");
}
}
}
[JsonProperty("exports")]
private ObservableCollection<SocialExportData> exports;
public ObservableCollection<SocialExportData> Exports
{
get
{
return exports;
}
set
{
if (exports != value)
{
exports = value;
RaisePropertyChanged("Exports");
}
}
}
//Event handling
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string property)
{
//Console.WriteLine("Updated");
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(property));
}
}
In another class, I have a method to deserialize to a global instance of my JSON class. It looks like this:
public SocialExportJSON socialExportData;
private async void DownloadAndDeserializeJSONAsync()
{
try
{
//Create a web client with the supplied credentials
var exportClient = new WebClient { Credentials = new NetworkCredential(uName, pw), Encoding = Encoding.UTF8};
//Create a task to download the JSON string and wait for it to finish
var downloadTask = Task.Run(() => exportClient.DownloadString(new Uri(eURL)));
downloadTask.Wait();
//Get the string from the task
var JSONString = await downloadTask;
//Create a task to deserialize the JSON from the last task
var DeserializeTask = Task.Run(() => JsonConvert.DeserializeObject<SocialExportJSON>(JSONString));
DeserializeTask.Wait();
SocialExportJSON sej = await DeserializeTask;
//Check the timestamp first to see if we should change the data
if(socialExportData == null)
{
//Get the data from the task
socialExportData = await DeserializeTask;
}
else if(sej.ModifiedTimestamp != socialExportData.ModifiedTimestamp)
{
//Get the data from the task
SocialExportJSON newData = await DeserializeTask;
GetNewItems(newData);
SetNewData(newData);
//Call the exportUpdated event when the task has finished
exportUpdated();
}
}
catch (Exception e)
{
MessageBox.Show(e.Message.ToString());
}
}
In my SetNewData function, shown below, I use reflection to set the properties of my global class. Because I'm setting the whole collection rather than iterating through each of the properties in each of the classes, I can't use the CollectionChanged event to find new items.
public void SetNewData(SocialExportJSON newData)
{
//Loop through each of the properties and copy from source to target
foreach (PropertyInfo pi in socialExportData.GetType().GetProperties())
{
if (pi.CanWrite)
{
pi.SetValue(socialExportData, pi.GetValue(newData, null), null);
}
}
}
Is there a way I can modify my SetNewData function in such a way that it calls CollectionChanged? If not, what would be the best way to go about getting any new additions to my collection of Item2?
In my Main function. I create an instance of my class called SocialExport like so:
SocialExport s = new SocialExport("http://example.json", "example", "example");.
This class is where the global instance of my JSON class is contained, and my event handler is added like so
s.socialExportData.Exports[0].Items.CollectionChanged += CollectionChanged;
Then you are hooking up an event handler for the CollectionChanged event for that particular instance of ObservableCollection<Item2>.
If you create a new ObservableCollection<Item2>, you obviously must hook up an event handler to this one as well. The event handler that is associated with the old object won't be invoked when new items are added to the new instance.
So whenever a new ObservableCollection<Item2> is created, using deserialization or not, you should hook up a new event handler.
You could probably do this in your DownloadAndDeserializeJSONAsync method. The other option would be to create only one instance of the collection and remove and add items from/to this one.
I am trying to reach a foreach but my program never gets inside because my ICollection Coletores is always empty even if I put a lot of stuff in there.
The code where I want to get inside and it is always empty (I want to get inside the second foreach):
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
if (NavigationContext.QueryString.TryGetValue("email", out email))
{
//MessageBox.Show(email);
List<HyperlinkButton> listaLinks = new List<HyperlinkButton>();
AppDataContext db = new AppDataContext();
int i = 0;
HyperlinkButton aux = new HyperlinkButton();
foreach (Pessoa pessoa in db.Pessoas)
{
if (pessoa.Email == email)
{
foreach (Coletor coletor in pessoa.Coletores)
{
aux.Content = "Coletor " + (i + 1).ToString();
aux.FontSize = 24;
aux.NavigateUri = new Uri("/OcorrenciasPage.xaml?coletorId=" + coletor.Id.ToString(), UriKind.RelativeOrAbsolute);
listaLinks.Add(aux);
i++;
}
}
}
ListBox coletores = new ListBox();
coletores.ItemsSource = listaLinks;
stcList.Children.Add(coletores);
}
base.OnNavigatedTo(e);
}
Now the code that I am adding data:
if (txtLat.Text != "" && txtLong.Text != "" && rdNorte.IsChecked == true || rdSul.IsChecked == true && rdLeste.IsChecked == true || rdOeste.IsChecked == true)
{
foreach (var pessoa in db.Pessoas)
{
if (pessoa.Email == email)
{
pessoa.Coletores.Add(coletor);
}
}
db.Coletores.InsertOnSubmit(coletor);
db.SubmitChanges();
NavigationService.Navigate(new Uri("/ColetoresPage.xaml?email=" + email, UriKind.RelativeOrAbsolute));
}
Now, my Pessoa class:
public class Pessoa : INotifyPropertyChanged
{
private int _id;
[Column(IsDbGenerated = true, IsPrimaryKey = true)]
public int Id {
get { return _id;}
set { _id = value;
OnPropertyChanged("Id");
}
}
private string _nome;
[Column]
public string Nome
{
get { return _nome; }
set { _nome = value;
OnPropertyChanged("Nome");
}
}
private string _email;
[Column]
public string Email
{
get { return _email; }
set { _email = value;
OnPropertyChanged("Email");
}
}
private string _senha;
[Column]
public string Senha { get { return _senha; }
set { _senha = value;
OnPropertyChanged("Senha");
}
}
private string _profissao;
[Column]
public string Profissao { get { return _profissao; }
set { _profissao = value;
OnPropertyChanged("Profissao");
}
}
private int _idade;
[Column]
public int Idade { get { return _idade; }
set { _idade = value;
OnPropertyChanged("Idade");
}
}
private string _endereco;
[Column]
public string Endereco { get { return _endereco; }
set { _endereco = value;
OnPropertyChanged("Endereco");
}
}
private string _cidade;
[Column]
public string Cidade { get { return _cidade; }
set { _cidade = value;
OnPropertyChanged("Cidade");
}
}
private string _estado;
[Column]
public string Estado { get { return _estado; }
set { _estado = value;
OnPropertyChanged("Estado");
}
}
private EntitySet<Coletor> _coletores = new EntitySet<Coletor>();
[Association(Name = "FK_Coletores_PessoaColetores", Storage = "_coletores", ThisKey = "Id", OtherKey = "pessoaId")]
public ICollection<Coletor> Coletores
{
get { return _coletores; }
set { _coletores.Assign(value); }
}
private EntitySet<PessoaColetor> _pessoaColetores = new EntitySet<PessoaColetor>();
[Association(Name = "FK_PessoaColetores_Pessoas", Storage = "_pessoaColetores", OtherKey = "pessoaId", ThisKey = "Id")]
private ICollection<PessoaColetor> PessoaColetores
{
get { return _pessoaColetores; }
set { _pessoaColetores.Assign(value); }
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string name)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(name));
}
}
}
The Coletores property on the Pessoa class looks alright. There is also a PessoaColetores property. Are you sure there has been no confusion between the two? Especially with intellisense one might dot or tab the wrong one.
Have you put a break point on the line that actually adds coletors (second code snippet)? Maybe stuff is added to the wrong collection.
Cheers, B.
This approach seems to work half the time for me.
I can see these lines get executed in the debugger:
agencyListBox.DataBindings.Add(new Binding("DataSource", this.Data.Agencies, "AvailableAgencies"));
agencyListBox.DataBindings.Add(new Binding("SelectedItem", this.Data.Agencies, "SelectedAgency", false, DataSourceUpdateMode.OnPropertyChanged));
The agencies class looks like this:
public AgencyType SelectedAgency
{
get
{
return _selected;
}
set
{
_selected = value;
OnPropertyChanged("SelectedAgency");
}
}
public List<AgencyType> AvailableAgencies
{
get
{
return _availableList;
}
set
{
_availableList = value;
OnPropertyChanged("AvailableAgencies");
}
}
So the fields I reference in the binding do exist.
The DisplayMember is set to "Label" which is defined in the AgencyType class:
public event PropertyChangedEventHandler PropertyChanged;
private string _label { get; set; }
public string Label
{
get { return _label; }
set
{
_label = value;
OnPropertyChanged("Label");
}
}
private string _identifier { get; set; }
public string Identifier
{
get { return _identifier; }
set
{
_identifier = value;
OnPropertyChanged("Identifier");
}
}
public AgencyType()
{
Label = string.Empty;
Identifier = string.Empty;
}
private void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
The values are displayed as desired.
But then when I change the selection, data.Agencies.SelectedAgency is null!
Does anyone have any tips?
In project i user SQL CE, i have Table:
[Table]
public class Article : INotifyPropertyChanged, INotifyPropertyChanging
{
// Define _cid: private field, public property, and database column.
private int _aid;
[Column(DbType = "INT NOT NULL IDENTITY", IsDbGenerated = true, IsPrimaryKey = true)]
public int aid
{
get { return _aid; }
set
{
NotifyPropertyChanging("aid");
_aid = value;
NotifyPropertyChanged("aid");
}
}
// Define nameColor name: private field, public property, and database column.
private int _rid;
[Column]
public int rid
{
get { return _rid; }
set
{
NotifyPropertyChanging("rid");
_rid = value;
NotifyPropertyChanged("rid");
}
}
private string _title;
[Column]
public string title
{
get { return _title; }
set
{
NotifyPropertyChanging("title");
_title = value;
NotifyPropertyChanged("title");
}
}
private string _thumnail;
[Column]
public string thumnail
{
get { return _thumnail; }
set
{
NotifyPropertyChanging("thumnail");
_thumnail = value;
NotifyPropertyChanged("thumnail");
}
}
private string _DesScription;
[Column(DbType = "NTEXT")]
public string DesScription
{
get { return _DesScription; }
set
{
NotifyPropertyChanging("DesScription");
_DesScription = value;
NotifyPropertyChanged("DesScription");
}
}
private int _orderID;
[Column]
public int orderID
{
get { return _orderID; }
set
{
NotifyPropertyChanging("orderID");
_orderID = value;
NotifyPropertyChanged("orderID");
}
}
private string _pubDate;
[Column]
public string pubDate
{
get { return _pubDate; }
set
{
NotifyPropertyChanging("pubDate");
_pubDate = value;
NotifyPropertyChanged("pubDate");
}
}
private string _linkURL;
[Column]
public string linkURL
{
get { return _linkURL; }
set
{
NotifyPropertyChanging("linkURL");
_linkURL = value;
NotifyPropertyChanged("linkURL");
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
// Used to notify that a property changed
private void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
#region INotifyPropertyChanging Members
public event PropertyChangingEventHandler PropertyChanging;
// Used to notify that a property is about to change
private void NotifyPropertyChanging(string propertyName)
{
if (PropertyChanging != null)
{
PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
}
}
#endregion
}
when i Update Colum Thumnail , i have erros :
SQL Server does not handle comparison of NText, Text, Xml, or Image data types
because of special characters into database insert sequence trogn should I use BbType = "NTEXT"
Please Help me !
You could remove this column for concurrency checking by adding [Column(UpdateCheck = UpdateCheck.Never)] to this column.
See this blogpost about Linq to sql concurrency checking: http://blogs.msdn.com/b/matt/archive/2008/05/22/into-to-linq-to-sql-optimistic-concurrency.aspx