Develop Reference

Why am I receiving an System.InvalidCastException when I am trying to call my ShowStatement method?

I am able to add accounts of different types through another form to the list statements which I can then add to the list box lstaccounts. However, when I select an account in my list box and press the view statement button I get that exception on the 'lblBank.Text = ShowStatement((IStatement)lstAccounts.SelectedItem);' line... any idea why this could be happening?
public List<IStatement> statements;
private int accountCounter = 0;
private int statementsViewed = 0;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
statements = new List<IStatement>();
}
private void btnView_Click(object sender, EventArgs e)
{
if (lstAccounts.SelectedIndex > -1)
{
lblBank.Text = ShowStatement((IStatement)lstAccounts.SelectedItem);
statementsViewed += 1;
lblTotal.Text = statementsViewed.ToString();
}
}
private string ShowStatement(IStatement item)
{
String msg = "Account Number: " + item.AccountNumber + "\n"
+ "Name: " + item.AccountName + "\n" + item.PrintStatement();
return msg;
}
private void btnAddAccount_Click(object sender, EventArgs e)
{
Form2 form2 = new Form2();
if(form2.ShowDialog() == DialogResult.OK)
{
if (form2.txtValue.Text == "" && form2.txtMinMonthly.Text == "")
{
BankAccount b = form2.GetBankAccount();
statements.Add(b);
}
else if (form2.txtMinMonthly.Text == "")
{
InsurancePolicy i = form2.GetInsurancePolicy();
statements.Add(i);
}
else
{
PlatinumCurrent p = form2.GetPlatinumCurrent();
statements.Add(p);
}
foreach (IStatement os in statements)
{
lstAccounts.Items.Add(os.ToString());
accountCounter += 1;
}
}
}
The exact error I'm getting is: System.InvalidCastException: 'Unable to cast object of type 'System.String' to type 'TelephoneBanking.IStatement'.'

You added it as .ToString() in your btnAddAccount_Click. Try add the item, not the item.ToString().
private void btnAddAccount_Click(object sender, EventArgs e)
{
...
foreach (IStatement os in statements)
{
lstAccounts.Items.Add(os); // ###### removed os.ToString() ######
accountCounter += 1;
}
...

Adding a new line when checking a checkbox

When I click on a checkbox I want the next checkbox information to be displayed on a new line, I know how to do this with "\r\n" however when unchecking the box and rechecking the box, it adds a new line above the text moving the original text down by 1 line. https://imgur.com/a/IHDDG85
I've tried "\r\n" and Environment.NewLine
private void chkHamburger_CheckedChanged(object sender, EventArgs e)
{
if (chkHamburger.Checked == true)
{
txtHamburger.Enabled = true;
txtHamburger.Text = "";
txtHamburger.Focus();
txtOrder.Text += ("Hamburger");
}
else
{
txtHamburger.Enabled = false;
txtHamburger.Text = "0";
}
if (chkHamburger.Checked == false)
{
txtOrder.Text = txtOrder.Text.Replace("Hamburger", "");
}
}
private void chkCheeseBurger_CheckedChanged(object sender, EventArgs e)
{
if (chkCheeseBurger.Checked == true)
{
txtCheeseBurger.Enabled = true;
txtCheeseBurger.Text = "";
txtCheeseBurger.Focus();
txtOrder.Text += ("Cheese Burger");
}
else
{
txtCheeseBurger.Enabled = false;
txtCheeseBurger.Text = "0";
}
if (chkCheeseBurger.Checked == false)
{
txtOrder.Text = txtOrder.Text.Replace("Cheese Burger", "");
}
}
I want the text of a checkbox to be displayed on a new line but when rechecking the box a whitespace should not appear above it.

I suggest you to use a List<string> where you add or remove your orders. Then it is easy to rebuild the txtOrder data with a single line of code using string.Join
List<string> orders = new List<string>();
private void chkHamburger_CheckedChanged(object sender, EventArgs e)
{
txtHamburger.Enabled = chkHamburger.Checked;
if (chkHamburger.Checked)
{
txtHamburger.Text = "";
txtHamburger.Focus();
orders.Add("Hamburger");
}
else
{
txtHamburger.Text = "0";
orders.Remove("Hamburger");
}
UpdateOrders();
}
private void chkCheeseBurger_CheckedChanged(object sender, EventArgs e)
{
txtCheeseBurger.Enabled = chkCheeseBurger.Checked;
if (chkCheeseBurger.Checked)
{
txtCheeseBurger.Text = "";
txtCheeseBurger.Focus();
orders.Add("Cheese Burger");
}
else
{
txtCheeseBurger.Text = "0";
orders.Remove("Cheese Burger");
}
UpdateOrders();
}
private void UpdateOrders()
{
txtOrders.Text = string.Join(Environment.NewLine, orders);
}

The best way to do this is to have a routine that builds the contents of the text independent of what just happened -- this you could use join or a loop to create the text contents.
Make this a function and call it when the check boxes change. The function loops over all your items and adds them to the output with the formatting and totals etc.

Could not find file 'c:\windows\system32\inetsrv\

I am using a aspx webpage with C# and I'm trying to point to a directory but when I do so, I get "Could not find file 'c:\windows\system32\inetsrv\2.txt'." But in my C# code, I am using:
currentStaffPosition = rolesRadioButton.SelectedItem.ToString();
string currentStaffDirectory = Server.MapPath(#"~\admin\applications\" + currentStaffPosition);
This code should point to C:\inetpub\wwwroot\admin\applications
Anyone know why or how this is happening? Thanks ahead of time.
Additional Code:
string currentStaffPosition = null;
string currentStaffDirectory = null;
protected void rolesRadioButton_SelectedIndexChanged(object sender, EventArgs e)
{
dropDownList.Items.Clear();
currentStaffPosition = rolesRadioButton.SelectedItem.ToString();
string currentStaffDirectory = Server.MapPath(#"~\admin\applications\" + currentStaffPosition);
string[] staffApplications = Directory.GetFiles(currentStaffDirectory);
foreach (string apps in staffApplications)
{
dropDownList.Items.Add(new ListItem(Path.GetFileNameWithoutExtension(apps)));
}
}
protected void dropDownList_SelectedIndexChanged(object sender, EventArgs e)
{
string currentSelectedApp = currentStaffDirectory + dropDownList.SelectedItem + ".txt";
string currentLine;
StreamReader applicationReader = new StreamReader(currentSelectedApp);
while ((currentLine = applicationReader.ReadLine()) != null)
{
if (currentLine.Contains("First Name:"))
forumUsernameTextBox.Text = currentLine.Replace("First Name: ", "");
}
applicationReader.Close();
}

Putting restrictions on deleting hashtable

I have a hashtable in my forms. So basically I have 2 button Add and Delete. When I put info in the textbox and add it adds it in the hashtable. But when I click delete it deletes it and when there's no value in it, it shows an error.
Question: So what I want to do is that when I put info in textBox1 which is not added in the Hashtable, it should give an error otherwise if the value is already added, it should just delete it.
public Form1()
{
InitializeComponent();
}
Hashtable Info = new Hashtable();
private void button1_Click(object sender, EventArgs e)
{
string a = textBox1.Text;
string b = textBox2.Text;
if (a == "" && b == "" || a == "" || b == "")
{
MessageBox.Show("Missing Input!");
}
else
{
MessageBox.Show("Added successfully");
label4.Text = a + " " + b;
}
}
private void button4_Click(object sender, EventArgs e)
{
string a = textBox1.Text;
string b = textBox2.Text;
if (a == "")
{
MessageBox.Show("Missing Value");
}
else if(Info.ContainsKey(a)) // but this deletes it even if the value has not been added
{
MessageBox.Show(textBox1.Text + "has been removed");
Info.Remove(a);
}
}
For example: If I add 2 in Hashtable and try to delete 3, it will still delete it just because there's some value in the textBox.

public Form1()
{
InitializeComponent();
}
Hashtable Info = new Hashtable();
private void AddToHashTable_Click(object sender, EventArgs e)
{
string a = textBox1.Text;
string b = textBox2.Text;
if (a == "" || b == "")
{
MessageBox.Show("Missing Input!");
}
else if(Info.ContainsKey(a) || Info.ContainsKey(b))
{
MessageBox.Show("Hash table already contain this key");
}
else
{
Info.Add(a);
Info.Add(b);
MessageBox.Show("Added successfully");
label4.Text = a + " " + b;
}
}
private void DeleteFromHashTable_Click(object sender, EventArgs e)
{
string a = textBox1.Text;
string b = textBox2.Text;
if (a == "")
{
MessageBox.Show("Missing Value");
}
else if(Info.ContainsKey(a)) // but this deletes it even if the value has not been added
{
MessageBox.Show(a + " has been removed");
Info.Remove(a);
}
else
{
MessageBox.Show(a + " is not part of the hash table");
}
//same check here for b
if (b == "")
{
MessageBox.Show("Missing Value");
}
else if(Info.ContainsKey(b)) // but this deletes it even if the value has not been added
{
MessageBox.Show(b + " has been removed");
Info.Remove(b);
}
else
{
MessageBox.Show(b + " is not part of the hash table");
}
}
I change the code a little bit. You miss some crucial things. Like check if the keys are already exist in the HashTable when you try to add them. If you try to add existing key exception will occur. Also I changed name of the methods, you miss to add the both text boxes in the hash table.

ICallbackEventHandler, RaiseCallbackEvent not firing

I have the following Javascript:
function processText(n)
{
CallServer("1" + n.id + "&" + n.value, "");
}
function ReceiveServerData(arg, context)
{
alert(arg);
}
With this for my code-behind:
protected void Page_Load(object sender, EventArgs e)
{
ClientScriptManager cm = Page.ClientScript;
String cbRef = cm.GetCallbackEventReference(this, "arg", "ReceiveServerData", "context");
String callbackscript = "function CallServer(arg, context) {" + cbRef + "; }";
cm.RegisterClientScriptBlock(this.GetType(), "CallServer", callbackscript, true);
if (Request.QueryString["stationID"] != null)
{
isIndividual = true;
stationID = Request.QueryString["stationID"];
EncodeDecode objServers = new EncodeDecode(HttpContext.Current.Server.MapPath("~/App_Data/"));
if (!IsPostBack)
{
List<IServerConfig> serverConfig = objServers.GetServerConfiguration(stationID);
Session["ServerConfig"] = serverConfig;
Session["dctPropertyControls"] = new Dictionary<string, PropertyObj>();
}
BindDynamicControls(Session["ServerConfig"] as List<IServerConfig>);
}
}
public void RaiseCallbackEvent(String eventArgument)
{
int iTyped = int.Parse(eventArgument.Substring(0, 1).ToString());
if (iTyped != 0) //Process Text Fields
{
string controlName = eventArgument.Substring(1, eventArgument.IndexOf("&")).ToString();
string controlValue = eventArgument.Substring(eventArgument.IndexOf("&")).ToString();
//Txtid += -1;
Dictionary<string, PropertyObj> dctPropertyObj = Session["dctPropertyControls"] as Dictionary<string, PropertyObj>;
PropertyObj propertyObj = dctPropertyObj[controlName];
propertyObj.property.SetValue(propertyObj.owner, controlValue, null);
this.sGetData = "Done";
}
}
public String GetCallbackResult()
{
return this.sGetData;
}
processText gets fired and works, however RaiseCallbackEvent never fires. Any ideas?

Apparently, any sort of validation error will cause this, though the page will never tell you about it. In my case, I had two datalists on the page with the same id. I had to debug the javascript and read the xmlRequest to see the error.

Sorry if replying late but may help others..
ValidationRequest="false" at .aspx page may sort out this unidentified problem.