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prevent shortcuts with wpf webbrowser

hey I have a problem with my wpf webbrowser. I dont want that you can press shortcuts like "CRTL + N" for a new tab for example. I already found out how to do it, but if I want to handle more shortcuts it will only prevent the last one. I know that this will be very simple but I dont know how to fix it at the moment. Here is my code:
e.Handled = e.Key == Key.N && e.KeyboardDevice.Modifiers == ModifierKeys.Control;
e.Handled = e.Key == Key.O && e.KeyboardDevice.Modifiers == ModifierKeys.Control;
e.Handled = e.Key == Key.OemMinus && e.KeyboardDevice.Modifiers == ModifierKeys.Control;
e.Handled = e.Key == Key.OemPlus && e.KeyboardDevice.Modifiers == ModifierKeys.Control;
e.Handled = e.Key == Key.Subtract && e.KeyboardDevice.Modifiers == ModifierKeys.Control;
e.Handled = e.Key == Key.Add && e.KeyboardDevice.Modifiers == ModifierKeys.Control;

You need to OR together your conditions.
e.Handled = ((e.Key == Key.N) && (e.KeyboardDevice.Modifiers == ModifierKeys.Control)) ||
((e.Key == Key.O) && (e.KeyboardDevice.Modifiers == ModifierKeys.Control)) ||
((e.Key == Key.OemMinus) && (e.KeyboardDevice.Modifiers == ModifierKeys.Control)) ||
((e.Key == Key.OemPlus) && (e.KeyboardDevice.Modifiers == ModifierKeys.Control)) ||
((e.Key == Key.Subtract) && (e.KeyboardDevice.Modifiers == ModifierKeys.Control)) ||
((e.Key == Key.Add) && (e.KeyboardDevice.Modifiers == ModifierKeys.Control));
As Modifier CTRL appears to be common, this can be separated out from the keys & the simplified code would be something like
e.Handled = (e.KeyboardDevice.Modifiers == ModifierKeys.Control) &&
((e.Key == Key.N) || (e.Key == Key.O) || (e.Key == Key.OemMinus) || ...... )
Note that I have added brackets that some people will say are unnecessary, but I prefer them for readability.

How to break if-else-if using C#

How do I break if-else-if.....Why its not working? its just checking all the conditions instead of performing the tasks. following is my code. I have checked it through breakpoints its moving to all conditions why it doesn't get stop after meeting the correct condition. even it is not going into the if activity it just read all the conditions and do nothing at the end.
private void ShowHash()
{
inpic = pb_selected.Image;
Bitmap image = new Bitmap(inpic);
byte[] imgBytes = new byte[0];
imgBytes = (byte[])converter.ConvertTo(image, imgBytes.GetType());
string hash = ComputeHashCode(imgBytes);
txt_selectedText.Text = hash;
GetHash();
}
private void GetHash()
{
if (txt_sel1.Text == null && (txt_sel2.Text == null || txt_sel3.Text == null || txt_sel4.Text == null || txt_sel5.Text == null ))
{
txt_sel1.Text = txt_selectedText.Text;
return;
}
else if (txt_sel1.Text != null && (txt_sel2.Text == null || txt_sel3.Text == null || txt_sel4.Text == null || txt_sel5.Text == null))
{
txt_sel2.Text = txt_selectedText.Text;
return;
}
else if (txt_sel2.Text != null && (txt_sel3.Text == null || txt_sel4.Text == null || txt_sel5.Text == null))
{
txt_sel3.Text = txt_selectedText.Text;
return;
}
else if (txt_sel3.Text != null && (txt_sel4.Text == null || txt_sel5.Text == null))
{
txt_sel4.Text = txt_selectedText.Text;
return;
}
else if (txt_sel4.Text != null && (txt_sel5.Text == null))
{
txt_sel5.Text = txt_selectedText.Text;
return;
}
}

I strongly suspect the problem is that the Text property is never null for any of txt_sel*. Assuming these are text boxes in a UI, it's much more likely that if there's no text in the text box, the Text property will return "" instead of null. That's the way most UI frameworks handle empty controls.
I would also suggest extracting the conditions into local variables first:
bool hasSel1 = txt_sel1.Text != "";
bool hasSel2 = txt_sel2.Text != "";
bool hasSel3 = txt_sel3.Text != "";
bool hasSel4 = txt_sel4.Text != "";
bool hasSel5 = txt_sel5.Text != "";
if (!hasSel1 && (!hasSel2 || !hasSel3 || !hasSel4 || !hasSel5)
{
...
}
And ideally, give your controls more meaningful names - a collection of variables with the same prefix but then a numeric suffix is very rarely a good idea, in terms of readability.

Reason:
If there is nothing in those textboxes, textbox.Text will return an empty string ("") not null.
Solution:
Check against "" not null:
private void GetHash()
{
if (txt_sel1.Text == "" && (txt_sel2.Text == "" || txt_sel3.Text == "" || txt_sel4.Text == "" || txt_sel5.Text == ""))
{
txt_sel1.Text = txt_selectedText.Text;
return;
}
else if (txt_sel1.Text != "" && (txt_sel2.Text == "" || txt_sel3.Text == "" || txt_sel4.Text == "" || txt_sel5.Text == ""))
{
txt_sel2.Text = txt_selectedText.Text;
return;
}
....
....
EDIT: You don't have to do ==true for boolean variables. If statement checks it against true by default. Use ! to check against false:
if (hasValue1 && (hasValue2 || hasValue3 || hasValue4 || hasValue5))
{
txt_sel1.Text = txt_selectedText.Text;
return;
}
else if (hasValue2 && (!hasValue1 ||hasValue3 || hasValue4 || hasValue5))
{
txt_sel2.Text = txt_selectedText.Text;
return;
}
else if (hasValue3 && (!hasValue1 || hasValue2 || hasValue4 || hasValue5))
{
txt_sel3.Text = txt_selectedText.Text;
return;
}
....
....

I think for string better to use inbuild null and whitespace check function:
bool hasValue1 = string.IsNullOrWhiteSpace(txt_sel1.Text);
bool hasValue2= string.IsNullOrWhiteSpace(txt_sel2.Text);
bool hasValue3= string.IsNullOrWhiteSpace(txt_sel3.Text);
bool hasValue4= string.IsNullOrWhiteSpace((txt_sel4.Text);
bool hasValue5 = string.IsNullOrWhiteSpace(txt_sel5.Text);
And then define if condition on these bool. This case can handle unexpected null or white space values.

That is bacause it probably doesn't find any of those conditions true.
If it would find a true condition it would execute that if block and won't event check the others.

To add to what others have said, you should really have a final else statement in there to catch issues such as this:
else
{
throw new InvalidOperationException("My If Statement is Broken");
}

Thanks to you all! My problem is solved by changing the conditions and your suggested alteration, following is the code may be helped some beginner like me.
private void GetHash()
{
bool hasValue1 = string.IsNullOrWhiteSpace(txt_sel1.Text);
bool hasValue2 = string.IsNullOrWhiteSpace(txt_sel2.Text);
bool hasValue3 = string.IsNullOrWhiteSpace(txt_sel3.Text);
bool hasValue4 = string.IsNullOrWhiteSpace(txt_sel4.Text);
bool hasValue5 = string.IsNullOrWhiteSpace(txt_sel5.Text);
if (hasValue1 && (hasValue2 || hasValue3 || hasValue4 || hasValue5))
{
txt_sel1.Text = txt_selectedText.Text;
return;
}
else if (hasValue2 && (!hasValue1 ||hasValue3 || hasValue4 || hasValue5 ))
{
txt_sel2.Text = txt_selectedText.Text;
return;
}
else if (hasValue3 && (!hasValue1 || !hasValue2 || hasValue4 || hasValue5 ))
{
txt_sel3.Text = txt_selectedText.Text;
return;
}
else if (hasValue4 && (!hasValue1 || !hasValue2 || !hasValue3 || hasValue5 ))
{
txt_sel4.Text = txt_selectedText.Text;
return;
}
else if (hasValue5 && (!hasValue1 || !hasValue2 || !hasValue3 || !hasValue4 ))
{
txt_sel5.Text = txt_selectedText.Text;
return;
}
else
{
CompareHash();
}
}

TabPages in accordance to CheckedListBox

I have a tabcontrol with 4 tabpages.I have a Checked list box with 8 items.I want to open the tabpages which were checked in the checkedlistbox.I tried like this.
private void clbScenario_ItemCheck(object sender, ItemCheckEventArgs e)
{
if (clbScenario.SelectedIndex == 0 || clbScenario.SelectedIndex == 1 || clbScenario.SelectedIndex == 2 || clbScenario.SelectedIndex == 3 || clbScenario.SelectedIndex == 4)
{
tabControl1.TabPages.Add(tp1);
}
else
HideTabPage(tp1);
if (clbScenario.SelectedIndex == 5 || clbScenario.SelectedIndex == 8)
{
tabControl1.TabPages.Add(tp2);
//ShowTabPage(tp2);
}
else
HideTabPage(tp2);
if (clbScenario.SelectedIndex == 6)
{
tabControl1.TabPages.Add(tp3);
}
else
HideTabPage(tp3);
if (clbScenario.SelectedIndex == 7)
{
tabControl1.TabPages.Add(tp4);
}
else
HideTabPage(tp4);
}
But the result is not as i thought.Please help me anyone

You need to use ItemCheckEventArgs e not the CheckedListBox itself. e.index is gonna give you which item is checked/unchecked and e.CurrentValue is gonna give you wheter is checked/unchecked. What you need to consider is if the e.CurrentValue is unchecked that means it's actually gonna be checked because this is showing value of the control before the process.
private void clbScenario_ItemCheck(object sender, ItemCheckEventArgs e)
{
if (e.Index >= 0 && e.Index <= 4)
{
if (e.CurrentValue.ToString() == "Unchecked") tabControl1.TabPages.Add(tp1);
else HideTabPage(tp1);
}
else if (e.Index == 5 || e.Index == 8)
{
if (e.CurrentValue.ToString() == "Unchecked") tabControl1.TabPages.Add(tp2);
else HideTabPage(tp2);
}
else if (e.Index == 6)
{
if (e.CurrentValue.ToString() == "Unchecked") tabControl1.TabPages.Add(tp3);
HideTabPage(tp3);
}
else if (e.Index == 7)
{
if (e.CurrentValue.ToString() == "Unchecked") tabControl1.TabPages.Add(tp4);
else HideTabPage(tp4);
}
}

Using Thread.Start() on a method that takes parameters and returns values

I call a particular function on multiple threads as follows:
int q = 0;
for (int j = 0; j < number; j++)
{
int copy = q;
int copy1 = j;
if (!display_status[copy1].Equals("NO") && (selection == "ALL" || (selection == "ALL-LAE" && license[copy1] != "") || (selection == "ALL-NON LAE" && license[copy1] == "") || (selection == "AVIONICS -ALL" && trade[copy1] == "Avionics") || (selection == "AVIONICS-NON LAE" && trade[copy1] == "Avionics" && license[copy1] == "") || (selection == "AVIONICS-LAE" && trade[copy1] == "Avionics" && license[copy1] != "") || (selection == "AIRFRAME-ALL" && trade[copy1] == "Airframes") || (selection == "AIRFRAME-NON LAE" && trade[j] == "Airframes" && license[j] == "") || (selection == "AIRFRAME-LAE" && trade[j] == "Airframes" && license[j] != "")))
{
int numberofprojects = numberc;
string[] nameofproj = listc[0].ToArray();
string[] name = list[0].ToArray();//list of manpower names
string man_name = name[copy1];//Name of manpower
List<string>[] lista = new List<string>[5];
string[] status = listc[13].ToArray();
thread[copy] = new Thread(() => {new_value[copy]=graph1threader(man_name,numberofprojects, nameofproj, status);});
thread[copy].Start();
q++;
}
}
graphthreader1() does not seem to be returning any value, as all elements of new_value hold the value 0 even after the function is called. What may be the reason? Is there a simple solution for this problem?

The most likely cause is that graph1threader has not finished yet, one way you can workaround this is by calling thread[copy].Join() but most likely this will defeat the purpose of using threads at all, another way will be by joining the first thread only at the end of the loop, but it depends on what you want to achieve with your code.

Avoid duplication of list items

I have a ListBox that contains items, which I have chosen from a ComboBox. When I chose an item from my ComboBox, it also removes that item in my ComboBox.
I have a button on my form, that let's me duplicate the selected item in my ListBox, giving me two of the same items in the ListBox.
I also have a button on my form, that let's me remove the selected item from my ListBox. If I remove an item from the ListBox, that item goes back to the ComboBox, but if I have duplicated the item and I remove both items from the ListBox, they both show up in the ComboBox.
I don't want it to be possible to have two of the same item in the ComboBox
Here's the code I have tried to use:
private void buttonRemove_Click(object sender, EventArgs e)
{
try
{
if (ComboBox.ToString().Contains("Chicken McNuggets"))
{
found = true;
}
if (!found)
{
ComboBox.Items.Add("Chicken McNuggets");
found = false;
}
ListBox.Items.Remove(ListBox.SelectedItem);
}
catch
{
MessageBox.Show(// Message);
}
}
This is my first time asking a question in here.
edit:
private void buttonRemove_Click(object sender, EventArgs e)
{
try
{
if ((String)listBox.SelectedItem == "Big Mac" || (String)listBox.SelectedItem == "Quarter Pounder" || (String)listBox.SelectedItem == "McFeast" || (String)listBox.SelectedItem == "Cheeseburger" || (String)listBox.SelectedItem == "Hamburger" || (String)listBox.SelectedItem == "Big Tasty Bacon" || (String)listBox.SelectedItem == "McChicken" || (String)listBox.SelectedItem == "Fillet-O-Fish" || (String)listBox.SelectedItem == "Chicken Nuggets")
{
comboBox.Items.Add(listBox.SelectedItem);
listBox.Items.Remove(listBox.SelectedItem);
}
else if ((String)listBox.SelectedItem == "BBQ dip" || (String)listBox.SelectedItem == "Cheddar dip" || (String)listBox.SelectedItem == "Gulerod" || (String)listBox.SelectedItem == "Hvidløgs dip" || (String)listBox.SelectedItem == "Karry dip" || (String)listBox.SelectedItem == "Ketchup" || (String)listBox.SelectedItem == "Pommes Frites Sauce" || (String)listBox.SelectedItem == "Sennep dip" || (String)listBox.SelectedItem == "Sursød dip" || (String)listBox.SelectedItem == "Æbler")
{
comboBox2.Items.Add(listBox.SelectedItem);
listBox.Items.Remove(listBox.SelectedItem);
}
else if ((String)listBox.SelectedItem == "Gulerodskage" || (String)listBox.SelectedItem == "Kanelsnegl" || (String)listBox.SelectedItem == "McDonut chokolade" || (String)listBox.SelectedItem == "Sundae m. chokoladesauce" || (String)listBox.SelectedItem == "McDonut sukkerovertræk" || (String)listBox.SelectedItem == "McFlurry Daim" || (String)listBox.SelectedItem == "McFlurry Smarties" || (String)listBox.SelectedItem == "Sundae m. jordbærdsauce" || (String)listBox.SelectedItem == "Sundae m. karamelsauce" || (String)listBox.SelectedItem == "Triple chokolade muffin" || (String)listBox.SelectedItem == "Vaffelis")
{
comboBox3.Items.Add(listBox.SelectedItem);
listBox.Items.Remove(listBox.SelectedItem);
}
else if (listBox.SelectedItem.ToString().Contains("Stor") || listBox.SelectedItem.ToString().Contains("Mellem") || listBox.SelectedItem.ToString().Contains("Lille") || listBox.SelectedItem.ToString().Contains("9") || listBox.SelectedItem.ToString().Contains("6") || listBox.SelectedItem.ToString().Contains("4"))
{
string objectToString = listBox.SelectedItem.ToString();
string[] ord = objektToString.Split(' ');
string selectedItem = listBox.SelectedItem;
var check = comboBox.Items.Cast<string>()
.ToList()
.FirstOrDefault(c => c.Contains(selectedItem));
if (check != null)
{
comboBox.Items.Add("Chicken McNuggets");
}
else
{
listBox.Items.Remove(selectedItem);
}
if (listBox.SelectedItem.ToString().Contains("Pommes Frites"))
comboBox2.Items.Add(ord[1] + " " + ord[2]);
else if (listBox.SelectedItem.ToString().Equals("Stor Coca-Cola") || listBox.SelectedItem.ToString().Equals("Mellem Coca-Cola") || listBox.SelectedItem.ToString().Equals("Lille Coca-Cola"))
comboBox4.Items.Add(ord[1]);
else if (listBox.SelectedItem.ToString().Contains("Milkshake"))
comboBox4.Items.Add(ord[1] + " " + ord[2] + " " + ord[3]);
else
comboBox4.Items.Add(ord[1] + " " + ord[2]);
listBox.Items.Remove(listBox.SelectedItem);
}
}
catch
{
MessageBox.Show(// Message);
}
}

We need to Cast to string the items from ComboBox so we can now easily check the ListBox.SelectedItem that already from ComboBox.Items.
private void buttonRemove_Click(object sender, EventArgs e)
{
try
{
string selectedItems = listBox1.SelectedItem.ToString();
var check = comboBox1.Items.Cast<string>()
.ToList()
.FirstOrDefault(c => c.Contains(selectedItems));
if (check != null)
{
}
else
{
comboBox.Items.Add("Chicken McNuggets");
listBox1.Items.Remove(selectedItems);
}
}
catch
{
//MessageBox.Show();
}
}