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WPF Datagrid SelectedIndex issue

I have a Datagrid to which I have added the DataGrid_SelectedCellsChanged event to show RowDetails for that specific cell when clicked.
This is working all fine as it should, but now I have on some that the event fires once, but after that it won't trigger it anymore if I select a cell in the same row. I checked in DataGrid_SelectCellColumnChanged and it won't change the value of the SelectedIndex (dg.SelectedIndex), even so I force it to with static values. Can someone maybe explain that, or have an idea what causes that problem?
Here is some of the code:
Create datagrid:
public static DataGrid AddDataGrid(ViewInfo viewInfo, System.Data.DataSet ds, UIElement parent, bool isReadOnly, bool setHighlight = true, System.Windows.Input.MouseButtonEventHandler clickEvent = null, EventHandler<DataGridCellEditEndingEventArgs> editEndEvent = null, string tagName = "", bool addDataContext = true)
{
try
{
DataTable dt = null;
////Reconfigure the Column Types in the Table for Sorting later
//if (DataGridExtension.CheckDataTableColumnTypeForDate(ds.Tables[0]))
//{
// dt = DataGridExtension.ReConfigureDataTableColumnType(ds.Tables[0]);
//}
//else
//{
// dt = ds.Tables[0];
//}
dt = ds.Tables[0];
DataGrid dg = new DataGrid
{
Name = "DataGrid__" + viewInfo.SprocName,
HorizontalAlignment = HorizontalAlignment.Left,
VerticalAlignment = VerticalAlignment.Top,
Margin = (tagName == "SubGrid") ? new Thickness(5, 5, 5, 10) : new Thickness(10, 0, 0, 0),
AutoGenerateColumns = true,
Style = TriggerStyleUtility.CreateStyle<DataGrid>(DataGrid.AlternatingRowBackgroundProperty, Brushes.LightGray),
AlternationCount = 2,
IsReadOnly = isReadOnly,
CanUserAddRows = false,
CanUserDeleteRows = false,
Visibility = Visibility.Visible
};
dg.CellStyle = TriggerStyleUtility.CreateStyle<DataGridCell>(DataGridCell.PaddingProperty, new Thickness(10), dg.CellStyle);
Style st = new Style(typeof(DataGridCell));
st.Setters.Add(new Setter(DataGridCell.PaddingProperty, new Thickness(10)));
//dg.CellStyle = st;
//set events
dg.AutoGeneratingColumn += DataGrid_AutoGeneratingColumn;
dg.Loaded += DataGrid_Loaded;
if (clickEvent != null) dg.MouseDoubleClick += clickEvent;
if (editEndEvent != null) dg.CellEditEnding += editEndEvent;
dg.Sorting += DataGrid_Sorting;
//ColumnCount = ds.Tables[0].Columns.Count;
ColumnCount = dt.Columns.Count;
List<object> list = new List<object>
{
viewInfo
};
if (addDataContext) list.InsertRange(0, new List<object>() { ds } );
dg.DataContext = list;
//dg.ItemsSource = ds.Tables[0].DefaultView;
dg.ItemsSource = dt.DefaultView;
UIElementExtensions.SetHighlight(dg, setHighlight);
//use this to evaluate if it is a SubGrid when Autogenerating Columns for ValueConverter
dg.Tag = tagName;
if (tagName == "SubGrid")
{
dg.MaxHeight = 600d;
dg.SelectedCellsChanged += SubDataGrid_SelectedCellsChanged;
}
//set event for Cell selection changed (triggers when selected row changes)
if (viewInfo.AddPNummerClick) dg.SelectedCellsChanged += DataGrid_SelectedCellsChanged;
//enable and set RowDetails, and events
//if (ds.Tables[0].Rows.Count > 0 && viewInfo.AddRowDetails)
if (dt.Rows.Count > 0 && viewInfo.AddRowDetails)
{
//set event for Cell selection changed (triggers when selected row changes)
if (!viewInfo.AddPNummerClick) dg.SelectedCellsChanged += DataGrid_SelectedCellsChanged;
//add event when cell is clicked (triggers on each cell)
st = new Style(typeof(DataGridCell));
st.Setters.Add(new EventSetter(DataGridCell.PreviewMouseLeftButtonDownEvent, new MouseButtonEventHandler(DataGrid_SelectCellColumnChanged)));
dg.CellStyle = st;
//add event for select row changes (used to bring focus to SubGrid)
st = new Style(typeof(DataGridRow));
st.Setters.Add(new EventSetter(DataGridRow.PreviewMouseLeftButtonDownEvent, new MouseButtonEventHandler(DataGrid_SelectRowDetails)));
dg.RowStyle = st;
//create default Template for RowDetails
DataGridExtension.CreateRowDetailsTemplate(dg);
}
//if no data set dummy item for NoDataTrigger
//if (dt.Rows.Count == 0)
if (ds.Tables[0].Rows.Count == 0)
{
dg.ItemsSource = new List<int> { -1 };
dg.Tag = "empty";
DataGridExtension.AddDataTemplate(dg, "Keine Daten gefunden!");
DataGridExtension.SetNoDataTrigger(dg);
}
//check parent and set appropriate position for DataGrid
if (parent.GetType() == typeof(DockPanel))
{
DockPanel.SetDock(dg, Dock.Top);
}
else
{
Grid.SetRow(dg, 1);
}
//add DatGrid to parent, so Highlights and DataGrid types can be processed (UpdateLayout)
ControlUtility.AddUIElement(parent, dg);
//highlight cells in DataGrid by max and lowest value in column
if (setHighlight) DataGridExtension.StartCellHighlight(dg, viewInfo);
//disable specific grid items (column, row, cell)
if (viewInfo.DisableTableItems != "") DataGridExtension.DisableGridElements(dg, viewInfo);
return dg;
}
catch (Exception ex)
{
FileLogger.HandleError("", false, true, "Error (DataGridUtility, AddDataGrid): " + Environment.NewLine + ex.Message, App._LogFilePath, App._LogFileName);
return null;
}
}
Code for DataGrid_SelectCellColumnChanged:
public static void DataGrid_SelectCellColumnChanged(object sender, MouseButtonEventArgs e)
{
try
{
DataGridCell dc = (DataGridCell)sender;
DataGrid dg = ControlUtility.FindParent<DataGrid>(dc);
UIElementExtensions.SetCurrentColumnIndex(dg, dc.Column.DisplayIndex);
if (dc.Column.DisplayIndex == 0) return;
int col = UIElementExtensions.GetCurrentColumnIndex(dg);
int row = UIElementExtensions.GetCurrentRowIndex(dg);
//change SelectedIndex to current Item Row, needed to trigger the cell changed event
if (dg.SelectedIndex == -1 || UIElementExtensions.GetCurrentColumnIndex(dg) == dg.SelectedIndex || (UIElementExtensions.GetCurrentColumnIndex(dg) != dg.SelectedIndex && UIElementExtensions.GetCurrentColumnIndex(dg) != 0))
{
var currentRowIndex = dg.Items.IndexOf(dg.CurrentItem);
bool changed = (UIElementExtensions.GetCurrentColumnIndex(dg) != dg.SelectedIndex && UIElementExtensions.GetCurrentColumnIndex(dg) != 0) ? true : false;
//if current RowIndex is different, set SelectedIndex to current row
//otherwise reset to -1 and back to current RowIndex, so cell change event can trigger
if (currentRowIndex != -1 && UIElementExtensions.GetCurrentColumnIndex(dg) != dg.SelectedIndex && !changed)
{
dg.SelectedIndex = currentRowIndex;
}
else
{
if (currentRowIndex == 0) return;
int test = UIElementExtensions.GetCurrentColumnIndex(dg);
// here it triggers normally the DataGrid_SelectedCellsChanged event, which usually works
dg.SelectedIndex = col; // UIElementExtensions.GetCurrentColumnIndex(dg);
/* trying to force it, but when debugging the SelectedIndex stays the same even after trying to set it static now,
and SelectedIndex has different value as test. It doesn't take the value????? */
if (dg.SelectedIndex != test) dg.SelectedIndex = 5;
App._CurrentColumnIndex = dg.SelectedIndex;
}
}
}
catch (Exception ex)
{
FileLogger.HandleError("", false, true, "Error (DataGridUtility, DataGrid_SelectedCellsChanged): " + Environment.NewLine + ex.Message, App._LogFilePath, App._LogFileName);
}
}
Class UIElementExtensions:
public class UIElementExtensions
{
//add Property "CurrentColumnIndex" and "CurrentRowIndex" to called UIElement
public static readonly DependencyProperty CurrentColumnIndexProperty = DependencyProperty.RegisterAttached("CurrentColumnIndex", typeof(int), typeof(UIElementExtensions), new FrameworkPropertyMetadata(null));
public static int GetCurrentColumnIndex(UIElement element)
{
if (element == null) throw new ArgumentNullException("element");
return (int)element.GetValue(CurrentColumnIndexProperty);
}
public static void SetCurrentColumnIndex(UIElement element, int value)
{
if (element == null) throw new ArgumentNullException("element");
element.SetValue(CurrentColumnIndexProperty, value);
}
public static readonly DependencyProperty CurrentRowIndexProperty = DependencyProperty.RegisterAttached("CurrentRowIndex", typeof(int), typeof(UIElementExtensions), new FrameworkPropertyMetadata(null));
public static int GetCurrentRowIndex(UIElement element)
{
if (element == null) throw new ArgumentNullException("element");
return (int)element.GetValue(CurrentRowIndexProperty);
}
public static void SetCurrentRowIndex(UIElement element, int value)
{
if (element == null) throw new ArgumentNullException("element");
element.SetValue(CurrentRowIndexProperty, value);
}
//add Property "Highlight" to called UIElement
public static readonly DependencyProperty HighlightProperty = DependencyProperty.RegisterAttached("Highlight", typeof(bool), typeof(UIElementExtensions), new FrameworkPropertyMetadata(null));
public static bool GetHighlight(UIElement element)
{
if (element == null) throw new ArgumentNullException("element");
return (bool)element.GetValue(HighlightProperty);
}
public static void SetHighlight(UIElement element, bool value)
{
if (element == null) throw new ArgumentNullException("element");
element.SetValue(HighlightProperty, value);
}
}
Code DataGrid_SelectedCellsChanged:
public static void DataGrid_SelectedCellsChanged(object sender, SelectedCellsChangedEventArgs e)
{
try
{
DataGrid dg = (DataGrid)sender;
if (dg.SelectedIndex == -1) return;
DataGridRow row = (DataGridRow)(dg.ItemContainerGenerator.ContainerFromItem(dg.SelectedItem));
//return if no row found (happens when sorting by column)
if (row == null) return;
// Getting the ContentPresenter of the row details
DataGridDetailsPresenter presenter = ControlUtility.FindVisualChild<DataGridDetailsPresenter>(row);
Grid parent = ControlUtility.FindVisualChild<Grid>(presenter);
//update presenter Layout to get Grid if presenter is still null
if (parent == null)
{
presenter.UpdateLayout();
parent = ControlUtility.FindVisualChild<Grid>(presenter);
}
DataRowView dataRow = (DataRowView)dg.SelectedItem;
//do stuff
}
}
Edit: To make this a little more clear, this normally works as it should, only on some loaded sprocs it doesn't work. I changed the sprocs on which it doesn't work with code from where it works, but the problem consists, so that can't be the issue. Also if I click another cell in another row, than it works again, but again only for one time. On other sprocs it always works.
Also how can a field (public int SelectedIndex { get; set; }) not be forced to take a value? That's what irritates me the most on it.
FYI: the problem is in the DataGrid_SelectCellColumnChanged event. When SelectedIndex is changed here. This normally triggers the DataGrid_SelectedCellsChanged, when it works.
I appreciate any help on this.

How to bind dynamically created text box?

I'm trying to create pricelist for hotel. I'm having a list of dates, and list of room types in hotel. That lists can contain random number of elements. That is created dynamically, and here is the code:
private void CreateControls() { var colIndex = 0;
var vrsteSoba = _Presenter.VrstaSobeDto.ToArray();
foreach (var bindingItem in vrsteSoba)
{
var lbl = new Label()
{
Width = LABEL_WIDTH,
Height = LABEL_HEIGHT - 5,
Left = 10,
Top = 30 + colIndex * (EDIT_BOX_HEIGHT + SPACE_BETWEEN_CONTROL),
Text = bindingItem
};
_dataPanel.Controls.Add(lbl);
colIndex++;
}
int a = 1;
foreach (var date in _Presenter.CeneTarifa)
{
int y = 0;
var panel = new Panel
{
Height = PANEL_HEIGHT * (vrsteSoba.Length-4),
Width = EDIT_BOX_WIDTH,
Left = a * (EDIT_BOX_WIDTH + SPACE_BETWEEN_CONTROL + 50),
Top = 5
};
_dataPanel.Controls.Add(panel);
var label = new Label
{
Height = EDIT_BOX_HEIGHT,
Location = new Point(0, 10),
Text = date.Datum,
Margin = new Padding(0)
};
panel.Controls.Add(label);
int index = 0;
foreach (var item in date.VrstaSobeCena)
{
var box = new TextBox();
panel.Controls.Add(box);
box.Height = EDIT_BOX_HEIGHT;
box.Width = EDIT_BOX_WIDTH;
box.Location = new Point(0, 30 + y * (EDIT_BOX_HEIGHT + SPACE_BETWEEN_CONTROL));
box.DataBindings.Add(new Binding(nameof(box.Text), date, date.Cena[index].Cena1));
y++;
index++;
}
++a;
}
_dataPanel.AutoScroll = true;
}`
Here is image of that representation.
Now I'm facing a problem of data binding. I need to bind price, two way, for each text box. And I'm stuck.
I have tried to bind it to property name, but then all boxes get same value. If I try to bind it to value via index, I'm getting error
Cannot bind to the property or column 34 on the DataSource. Parameter name: dataMember
Code below is used to fill model that is used in presenter
` private void FillCenePoTarifi() { var sobeArr = VrstaSobeDto.ToArray();
foreach (var datum in Datumi)
{
var dictionary = new Dictionary<string, decimal>();
var cene = new List<Cena>();
foreach (var item in sobeArr)
{
var tarif = _Tarife.Where(x => x.SifTarife == item).FirstOrDefault();
if (tarif != null)
_SastavTarife = HotelierServerLocal.Default.TarifaViewBlo.GetSastaveTarife(tarif.IdTarife);
//proveriti ovu logiku
var cena = _SastavTarife.Where(x => x.Cena1 != 0).Select(c => c.Cena1).FirstOrDefault();
cene.Add(new Cena { Cena1 = cena.ToString()});
dictionary.Add(item, cena);
}
var model = new CenePoTarifi
{
Datum = datum,
VrstaSobeCena = dictionary,
Cena = cene
};
CeneTarifa.Add(model);
}
}`
Finally here are classes that use as model.
` public class CenePoTarifi{
public Dictionary<string, decimal> VrstaSobeCena { get; set; } = new Dictionary<string, decimal>();
public string Datum { get; set; }
private List<Cena> _Cena;
public List<Cena> Cena
{
get => _Cena;
set
{
_Cena = value;
NotifyPropertyChanged("Cena");
}
}
public class Cena :
{
private string _Cena1;
public string Cena1
{
get => _Cena1;
set
{
_Cena = value;
NotifyPropertyChanged("Cena1");
}
}
}`
Does anyone has any suggestions?

Your question is: How to bind dynamically created text box. Here is one tested way for accomplishing that specific task.
First create some textboxes dynamically:
public MainForm()
{
InitializeComponent();
buttonRandom.Click += (sender, e) => generateRandomList();
}
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
List<TextBox> tmp = new List<TextBox>();
for (int column = 1; column < tableLayoutPanel.ColumnCount; column++)
{
for (int row = 1; row < tableLayoutPanel.RowCount; row++)
{
TextBox textBox = new TextBox { Anchor = (AnchorStyles)0xF };
tableLayoutPanel.Controls.Add(textBox, column, row);
tmp.Add(textBox);
textBox.KeyDown += onAnyTextBoxKeyDown;
}
}
_textboxes = tmp.ToArray();
// Generate first dataset
generateRandomList();
}
TextBox[] _textboxes = null;
Then, whenever a new random list is generated, clear any old text and databindings from every TextBox before creating a new data binding for it.
public static Random Rando { get; } = new Random(2);
private void generateRandomList()
{
// Clear ALL the data + bindings for ALL the textboxes.
foreach (var textbox in _textboxes)
{
textbox.Clear();
textbox.DataBindings.Clear();
}
// Generate and create new bindings
int count = Rando.Next(1, 79);
for (int i = 0; i < count; i++)
{
var textbox = _textboxes[i];
VrstaSobeCena vrstaSobeCena =
new VrstaSobeCena{ Sobe = (Sobe)tableLayoutPanel.GetRow(textbox) };
textbox.Tag = vrstaSobeCena;
textbox.DataBindings.Add(
new Binding(
nameof(TextBox.Text),
vrstaSobeCena,
nameof(VrstaSobeCena.Cena),
formattingEnabled: true,
dataSourceUpdateMode: DataSourceUpdateMode.OnPropertyChanged,
null,
"F2"
));
// TO DO
// ADD vrstaSobeCena HERE to the Dictionary<string, decimal> VrstaSobeCena
}
}
The classes shown in your code as binding sources may not bind correctly. One issue I noticed is that the property setters are failing to check whether the value has actually changed before firing the notification. Here's an example of doing that correctly. (For testing purposes I'm showing a Minimal Reproducible Sample "mock" version of a class that implements INotifyPropertyChanged.)
enum Sobe { APP4 = 1, APP5, STUDIO, SUP, APP6, STAND, STDNT, COMSTU, LUXSTU, APP4C, APP4L, APP62, APP6L }
class VrstaSobeCena : INotifyPropertyChanged
{
decimal _price = 100 + (50 * (decimal)Rando.NextDouble());
public decimal Cena
{
get => _price;
set
{
if (!Equals(_price, value))
{
_price = value;
OnPropertyChanged();
}
}
}
Sobe _sobe = 0;
public Sobe Sobe
{
get => _sobe;
set
{
if (!Equals(_sobe, value))
{
_sobe = value;
OnPropertyChanged();
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
Finally, one way to test the two-way binding is to intercept the [Enter] key.
private void onAnyTextBoxKeyDown(object sender, KeyEventArgs e)
{
if ((e.KeyCode == Keys.Enter) && (sender is TextBox textbox))
{
e.SuppressKeyPress = e.Handled = true;
VrstaSobeCena vrstaSobeCena = (VrstaSobeCena)textbox.Tag;
string msg = $"Price for {vrstaSobeCena.Sobe} is {vrstaSobeCena.Cena.ToString("F2")}";
BeginInvoke((MethodInvoker)delegate {MessageBox.Show(msg); });
SelectNextControl(textbox, forward: true, tabStopOnly: true, nested: false, wrap: true);
}
}

Create a List for storing the textbox:
List<TextBox> lstTextbox = new List<TextBox>();
Create a class object that stores the values of "Date" and "room type"
public class RoomTypeDate
{
public string RoomType = "";
public string DateRange = "";
}
Immediately after you created the textbox, assigned the RoomTypeDate info to the tag, add it to lstTextbox.
foreach (var item in date.VrstaSobeCena)
{
var box = new TextBox();
panel.Controls.Add(box);
box.Height = EDIT_BOX_HEIGHT;
box.Width = EDIT_BOX_WIDTH;
box.Location = new Point(0, 30 + y * (EDIT_BOX_HEIGHT + SPACE_BETWEEN_CONTROL));
box.DataBindings.Add(new Binding(nameof(box.Text), date, date.Cena[index].Cena1));
// add the box to the list
lstTextbox.Add(box);
// mark the box with RoomType and DateRange
RoomTypeDate rtd = new RoomTypeDate();
rtd.RoomType = "APP4"; // get the room type
rtd.DateRange = "1.6 - 30.6"; // get date range
box.Tag = rtd;
y++;
index++;
}
Now, to get and set the room price:
public void SetRoomPrice(decimal price, string roomType, string dateRange)
{
foreach (var tb in lstTextBox)
{
var rtd = (RoomTypeDate)tb.Tag;
if(rtd.RoomType == roomType && rtd.DateRange == dateRange)
{
tb.Text = price.ToString();
return;
}
}
}
public decimal GetRoomPrice(string roomType, string dateRange)
{
foreach (var tb in lstTextBox)
{
var rtd = (RoomTypeDate)tb.Tag;
if(rtd.RoomType == roomType && rtd.DateRange == dateRange)
{
return Convert.ToDecimal(rt.Text);
}
}
return 0m;
}
*code untested, might contains bugs

WPF validation run-time generated forms

I'm creating a WPF application which generates a form based on a model to edit it. I use reflection to go through all properties of the model to create inputfields for the properties. The GenerateForm method iterates through the properties and uses the SimpleInputFactory to generate input fields. I want to validate the input of the generated fields, but all validation methods require that you know what you are going to validate (either it's using generics or you have to specify it on the binding in the XAML). I want to validate the input based on attributes in the models. Is there any existing way of doing this? I could just make it myself, but if there is some existing way it would help.
Thanks in advance.
public static Grid GenerateForm(List<object> basisgegevensModels, AddOrEdit addOrEdit)
{
if (basisgegevensModels.Count <= 0)
return null;
Grid formGrid = new Grid();
formGrid.Margin = new Thickness(20,20,20,20);
formGrid.HorizontalAlignment = HorizontalAlignment.Stretch;
AddColumnToGrid(formGrid, GridUnitType.Star, 1);
AddColumnToGrid(formGrid, GridUnitType.Star, 3);
AddColumnToGrid(formGrid, GridUnitType.Star, 1);
AddColumnToGrid(formGrid, GridUnitType.Star, 3);
AddRowToGrid(formGrid, GridUnitType.Auto, 0);
var propertyInfos = new List<PropertyInfo>();
foreach (var propertyInfo in basisgegevensModels[0].GetType().GetProperties(BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.Instance))
{
var visibleAttribute = propertyInfo.GetCustomAttributes(typeof(Visible), false).Cast<Visible>().FirstOrDefault();
if (visibleAttribute == null || visibleAttribute.IsVisible)
propertyInfos.Add(propertyInfo);
}
int column = 0;
int row = 0;
foreach (var property in propertyInfos)
{
if (row >= Math.Ceiling((decimal)propertyInfos.Count / 2) && row != 0 && column != 2)
{
column = 2;
row = 0;
}
var displayNameAttribute = basisgegevensModels[0].GetType().GetProperty(property.Name).GetCustomAttributes(typeof(DisplayNameAttribute), false)
.Cast<DisplayNameAttribute>().FirstOrDefault();
string displayName;
if (displayNameAttribute != null)
displayName = displayNameAttribute.DisplayName;
else
displayName = property.Name;
bool isEditAllowed = true;
if (addOrEdit == AddOrEdit.Edit)
{
var editAllowed =
basisgegevensModels[0].GetType()
.GetProperty(property.Name)
.GetCustomAttributes(typeof (EditAllowed), false)
.Cast<EditAllowed>()
.FirstOrDefault();
if (editAllowed != null)
isEditAllowed = editAllowed.IsEditAllowed;
}
//add label for inputfield
TextBlock label = SimpleInputFieldFactory.CreateTextBlock(displayName, column, row);
label.VerticalAlignment = VerticalAlignment.Center;
formGrid.Children.Add(label);
column++;
//add input field
formGrid.Children.Add(SimpleInputFieldFactory.CreateInputField(basisgegevensModels, property, isEditAllowed, column, row, 300, HorizontalAlignment.Left));
column--;
row++;
if (column == 0)
{
AddRowToGrid(formGrid, GridUnitType.Auto, 0);
}
}
return formGrid;
}
SimpleInputFieldFactory Class:
public class SimpleInputFieldFactory
{
public static Control CreateInputField(List<object> basisgegevensModels, PropertyInfo property, bool editAllowed, int column, int row, double inputFieldWidth, HorizontalAlignment inputFieldHorAlignment)
{
Control inputField = null;
var triggers = new List<System.Windows.Interactivity.EventTrigger>();
var multiBinding = new MultiBinding();
multiBinding.NotifyOnSourceUpdated = true;
multiBinding.Mode = BindingMode.TwoWay;
multiBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
foreach (var basisgegevensModel in basisgegevensModels)
{
Binding binding = new Binding(property.Name)
{
UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged,
Source = basisgegevensModel,
Mode = BindingMode.TwoWay
};
multiBinding.Bindings.Add(binding);
}
//add inputfield
if (property.PropertyType == typeof(string) || property.PropertyType == typeof(int))
{
string valueAsString = "";
if (property.GetValue(basisgegevensModels[0]) != null)
valueAsString = property.GetValue(basisgegevensModels[0]).ToString();
inputField = CreateTextBox(valueAsString, column, row);
triggers.Add(new System.Windows.Interactivity.EventTrigger("EditValueChanged"));
}
else if (property.PropertyType == typeof(bool))
{
bool valueAsBool = false;
if (property.GetValue(basisgegevensModels[0]) != null)
valueAsBool = (bool)property.GetValue(basisgegevensModels[0]);
inputField = CreateCheckBox(valueAsBool, column, row);
triggers.Add(new System.Windows.Interactivity.EventTrigger("EditValueChanged"));
}
else if (property.PropertyType.BaseType == typeof(Enum))
{
int valueAsInt = 0;
if (property.GetValue(basisgegevensModels[0]) != null)
valueAsInt = (int)property.GetValue(basisgegevensModels[0]);
inputField = CreateDropDown(property.PropertyType, valueAsInt, column, row);
triggers.Add(new System.Windows.Interactivity.EventTrigger("EditValueChanged"));
((ComboBoxEdit)inputField).SelectedIndex = valueAsInt;
((ComboBoxEdit)inputField).IsTextEditable = false;
}
//add general settings, bindings and triggers
if (inputField != null)
{
inputField.Width = inputFieldWidth;
inputField.HorizontalAlignment = inputFieldHorAlignment;
inputField.Margin = new Thickness(5);
inputField.IsEnabled = editAllowed;
var multiEditAllowedAttribute = property.GetCustomAttributes(typeof(MultiEditAllowed), false)
.Cast<MultiEditAllowed>().FirstOrDefault();
//only add binding and trigger if 1 entity is selected OR multiedit is allowed
if (basisgegevensModels.Count == 1 || multiEditAllowedAttribute == null || multiEditAllowedAttribute.IsMultiEditAllowed)
{
multiBinding.Converter = new MultiEditValueConverter();
inputField.SetBinding(BaseEdit.EditValueProperty, multiBinding);
foreach (var trigger in triggers)
{
var action = new ActionMessage();
action.MethodName = "InputChanged";
trigger.Actions.Add(action);
Interaction.GetTriggers(inputField).Add(trigger);
}
}
else
{
inputField.IsEnabled = false;
}
return inputField;
}
return null;
}
public static List<string> GetEnumList(Type enumType)
{
if (!enumType.IsEnum)
{
return new List<string>();
}
return Enum.GetNames(enumType).ToList();
}
public static TextBlock CreateTextBlock(string text, int column, int row)
{
TextBlock textBlock = new TextBlock();
textBlock.Text = text;
Grid.SetColumn(textBlock, column);
Grid.SetRow(textBlock, row);
return textBlock;
}
private static TextEditBase CreateTextBox(string text, int column, int row)
{
TextEdit textBox = new TextEdit();
textBox.Text = text;
Grid.SetColumn(textBox, column);
Grid.SetRow(textBox, row);
return textBox;
}
private static CheckEdit CreateCheckBox(bool isChecked, int column, int row)
{
CheckEdit checkBox = new CheckEdit();
checkBox.IsChecked = isChecked;
Grid.SetColumn(checkBox, column);
Grid.SetRow(checkBox, row);
return checkBox;
}
private static ComboBoxEdit CreateDropDown(Type enumType, int value, int column, int row)
{
ComboBoxEdit dropDown = new ComboBoxEdit();
foreach (var enumValue in GetEnumList(enumType))
{
dropDown.Items.Add(enumValue);
}
dropDown.SelectedIndex = value;
Grid.SetColumn(dropDown, column);
Grid.SetRow(dropDown, row);
return dropDown;
}
}

Yes, you can use the System.ComponentModel.DataAnnotations for validation.
Documentation for the base namespace : MSDN: System.ComponentModel.DataAnnotations
Examples include RequiredAttribute and RangeAttribute.
Microsoft also provide an excellent example of how to provide validation feedback in realtime to the user in WPF using the ErrorTemplate and Binding in the following example: MSDN: Validation in MVVM using Data Annotations
I've also developed a small framework for my own purposes which incorporates these techniques - basically a base class where you need to decorate your VM with ValidationAttribute derived attributes and use the appropriate Binding and WPF takes care of the rest. GitHub: ValidatingBaseViewModel

Print lists in a list to excel, randomly stops printing after 0.5-6 lists. Comexpection 0x800AC472

First of all I have have some codes which is filling some lists of strings, after that it puts all the lists in 1 big list. Now when I want to print those lists in my excel sheets, it stops after pint half of the first list, or stops after print 5 and a half list, and it says: Exception from HRESULT: 0x800AC472.
There are already 30 tabs in the excel doc, so that is not the problem. Feel free to rename this title, Ihad no idea how to call this problem.
This is how I print my lists in excel:
for (int i = 0; i < ListofLists.Count; i++)
{
for (int j = 1; j <= ListofLists[i].Count; j++)
{
excelDataHandler.excel_setValue("A" + j, ListofLists[i][j-1], "", (i+1));
//A = cell, data of list, color of cell, sheetnumber
}
}
excel_setValue method:
public void excel_setValue(string cellname, string value, string color, int workSheet)
{
((Microsoft.Office.Interop.Excel._Worksheet)newWorkbook_First.Sheets[workSheet]).get_Range(cellname).set_Value(Type.Missing, value);
if (color == "red")
{
newSheets.get_Range(cellname).Interior.Color = System.Drawing.ColorTranslator.ToOle(System.Drawing.Color.Red);
}
}
I would appriciate any help with this problem. Thanks in asvance!

Here is my reflection code.
public static DataTable ClassToDataTable<T>() where T : class
{
Type classType = typeof(T);
List<PropertyInfo> propertyList = classType.GetProperties().ToList();
if (propertyList.Count < 1)
{
return new DataTable();
}
string className = classType.UnderlyingSystemType.Name;
DataTable result = new DataTable(className);
foreach (PropertyInfo property in propertyList)
{
DataColumn col = new DataColumn();
col.ColumnName = property.Name;
Type dataType = property.PropertyType;
if (IsNullable(dataType))
{
if (dataType.IsGenericType)
{
dataType = dataType.GenericTypeArguments.FirstOrDefault();
}
}
else
{ // True by default
col.AllowDBNull = false;
}
col.DataType = dataType;
result.Columns.Add(col);
}
return result;
}
public static DataTable ClassListToDataTable<T>(List<T> ClassList) where T : class
{
DataTable result = ClassToDataTable<T>();
if (result.Columns.Count < 1)
{
return new DataTable();
}
if (ClassList.Count < 1)
{
return result;
}
foreach (T item in ClassList)
{
ClassToDataRow(ref result, item);
}
return result;
}
public static void ClassToDataRow<T>(ref DataTable Table, T Data) where T : class
{
Type classType = typeof(T);
string className = classType.UnderlyingSystemType.Name;
// Checks that the table name matches the name of the class.
// There is not required, and it may be desirable to disable this check.
// Comment this out or add a boolean to the parameters to disable this check.
if (!Table.TableName.Equals(className))
{
return;
}
DataRow row = Table.NewRow();
List<PropertyInfo> propertyList = classType.GetProperties().ToList();
foreach (PropertyInfo prop in propertyList)
{
if (Table.Columns.Contains(prop.Name))
{
if (Table.Columns[prop.Name] != null)
{
row[prop.Name] = prop.GetValue(Data, null);
}
}
}
Table.Rows.Add(row);
}
public static bool IsNullable(Type Input)
{
if (!Input.IsValueType) return true; // Is a ref-type, such as a class
if (Nullable.GetUnderlyingType(Input) != null) return true; // Nullable
return false; // Must be a value-type
}

Display Null if datagridview Column is empty

I have a gridview with few column cells. all i want is to check an empty cells and write null by default. if some of the columns are not filled., i want a default null text to the specific cells that are ommited
I tried to create something like this but it is not working as i don't know how i can take it further
private void Gridview_Output_CellFormatting_1(object sender, DataGridViewCellFormattingEventArgs e)
{
string _Car = string.Empty;
string _Dealer = string.Empty;
string _Model = string.Empty;
int gridcount = Gridview.Rows.Count;
for (int i = 0; i < gridcount; i++)
{
_Car = "";
_Dealer = "";
_Model = "";
if (Gridview.Rows[i].Cells[1].Value == DBNull.Value)
{
_Car = "Null";
}
else
{
_Car = Gridview.Rows[i].Cells[1].Value.ToString();
}
if (Gridview.Rows[i].Cells[2].Value == DBNull.Value)
{
_Dealer = "Null";
}
else
{
_Dealer = Gridview.Rows[i].Cells[2].Value.ToString();
}
if (Gridview.Rows[i].Cells[4].Value == DBNull.Value)
{
_Model = "Null";
}
else
{
_Model = Gridview.Rows[i].Cells[4].Value.ToString();
}
}
}

foreach (DataGridViewRow dr in dataGridView1.Rows)
{
if (!dr.IsNewRow)
{
for (int c = 0; c <= dr.Cells.Count - 1; c++)
{
if (dr.Cells[c].Value == null)
{
dr.Cells[c].Value = "NULL TEXT";
}
}
}
}

You are looking for the DataGridView's CellFormatting event.
Try something like this :
private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e)
{
if (string.IsNullOrEmpty(e.Value as string))
{
e.Value = "NULL";
e.FormattingApplied = true;
}
}
If necessary, you can also add a column condition with the e.ColumnIndex property.