【发布时间】：2021-04-09 23:30:54
【问题描述】：
当我按下登录名并调用 LoginClick() 方法时，发生异常，这是在我使用 SSMS 将 SQL 数据库中的列名从“itemDescription”更改为“itemName”之后发生的，希望您能帮助我。我已经尝试了一切，并确保我在问这个问题之前进行了研究。我现在被困在这里几个小时了。不知道问题出在哪里。
LoginForm.cs
private void LoginClick()
{
if (MTBoxUsername.Text.Length == 0 || MTBoxPassword.Text.Length == 0)
{
MessageBox.Show("Please enter your username and password", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
else
{
if (!int.TryParse(MTBoxUsername.Text, out int j))
{
MessageBox.Show("Your username is your student number", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
return;
}
string username = MTBoxUsername.Text;
string password = MTBoxPassword.Text;
var student = (from s in DatabaseHelper.db.tblUsers
where s.username == long.Parse(username)
select s).First();
if (student != null)
{
if (BCrypt.CheckPassword(password, student.password))
{
MessageBox.Show("Login Succesful!", "INFORMATION", MessageBoxButtons.OK, MessageBoxIcon.Information);
this.Hide();
if (student.userType.Equals("STUDENT"))
{
var loginStudent = (from s in DatabaseHelper.db.tblStudents
where s.StudentNumber == long.Parse(username)
select s).First();
new StudentForm().Show();
}
else if (student.userType.Equals("ADMIN"))
{
new AdminForm().Show();
}
else if (student.userType.Equals("FACULTY"))
{
new StaffFormMain().Show();
}
}
else
{
MessageBox.Show("Invalid username or password", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
}
else
{
MessageBox.Show("Invalid username or password.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
}
}
StudentForm.cs
public StudentForm()
{
this.selectedStudent = (from s in DatabaseHelper.db.tblStudents
where s.StudentNumber == 2000013113
select s).First();
InitializeComponent();
materialSkinManager = MaterialSkin.MaterialSkinManager.Instance;
materialSkinManager.EnforceBackcolorOnAllComponents = true;
materialSkinManager.AddFormToManage(this);
materialSkinManager.Theme = MaterialSkin.MaterialSkinManager.Themes.LIGHT;
materialSkinManager.ColorScheme = new MaterialSkin.ColorScheme(MaterialSkin.Primary.Indigo500,
MaterialSkin.Primary.Indigo700,
MaterialSkin.Primary.Indigo100,
MaterialSkin.Accent.Pink200,
MaterialSkin.TextShade.WHITE);
}
private void RefreshCartList()
{
DgvCartList.Rows.Clear();
subTotal = 0;
foreach (OrderDetail item in cartList)
{
DgvCartList.Rows.Add(item.itemName,
item.quantity,
item.pricePerUnit,
item.total);
subTotal += item.total;
}
BtnCheckout.Enabled = cartList.Count > 0;
BtnClearCart.Enabled = cartList.Count > 0;
BtnRemoveItem.Enabled = cartList.Count > 0;
LabelSubTotal.Text = cartList.Count > 0 ? subTotal.ToString() : "";
}
private void ClearCart()
{
cartList.Clear();
RefreshCartList();
}
private void CmbItems_SelectedIndexChanged(object sender, EventArgs e)
{
LabelStockCount.Text = itemList[CmbItems.SelectedIndex].stocks.ToString();
LabelPrice.Text = itemList[CmbItems.SelectedIndex].price.ToString();
BtnAddToCart.Enabled = true;
}
private void BtnAddToCart_Click(object sender, EventArgs e)
{
if (CmbItems.SelectedIndex != -1)
{
tblItem selectedItem = itemList[CmbItems.SelectedIndex];
if (cartList.Count > 0)
{
foreach (OrderDetail item in cartList)
{
if (item.itemID.Equals(selectedItem.ID))
{
if (item.quantity == 99)
{
MessageBox.Show("You cannot add more than 99 items of the same type in cart.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
return;
}
if (item.quantity == selectedItem.stocks)
{
MessageBox.Show("You have reached the maximum number of stocks available.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
return;
}
item.quantity++;
RefreshCartList();
return;
}
}
}
cartList.Add(new OrderDetail
{
itemID = selectedItem.ID,
itemName = selectedItem.itemName,
quantity = 1,
pricePerUnit = selectedItem.price
});
RefreshCartList();
}
}
private void DgvCartList_RowEnter(object sender, DataGridViewCellEventArgs e)
{
selectedItemFromCart = DgvCartList.Rows[e.RowIndex].Cells[0].Value.ToString();
}
private void BtnRemoveItem_Click(object sender, EventArgs e)
{
DialogResult dialogResult = MessageBox.Show("Are you sure you want to remove '" + selectedItemFromCart + "' from your cart?",
"QUESTION", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (dialogResult == DialogResult.Yes)
{
foreach (OrderDetail item in cartList)
{
if (item.itemName.Equals(selectedItemFromCart))
{
cartList.Remove(item);
RefreshCartList();
return;
}
}
}
}
private void BtnClearCart_Click(object sender, EventArgs e)
{
DialogResult dialogResult = MessageBox.Show("Are you sure you want to clear your cart?", "QUESTION", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (dialogResult == DialogResult.Yes)
{
ClearCart();
}
}
private void BtnCheckout_Click(object sender, EventArgs e)
{
DialogResult dialogResult = MessageBox.Show("Are you sure you want to checkout? You cannot reverse this action once done.", "QUESTION", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (dialogResult == DialogResult.Yes)
{
var newOrder = new tblOrder
{
studentId = selectedStudent.StudentNumber,
orderStatus = "PENDING",
orderDate = DateTime.Today.Date,
totalPrice = subTotal
};
DatabaseHelper.db.tblOrders.InsertOnSubmit(newOrder);
DatabaseHelper.db.SubmitChanges();
var st = (from tbl in itemList
join cart in cartList on tbl.ID equals cart.itemID
select new {
tbl.ID,
cart.quantity
}).ToList();
foreach(var item in st)
{
var reduceStock = (from s in DatabaseHelper.db.tblItems
where s.ID == item.ID
select s).First();
reduceStock.stocks -= item.quantity;
}
DatabaseHelper.db.SubmitChanges();
foreach (OrderDetail item in cartList)
{
var newOrderDetail = new tblOrderDetail
{
orderIdRef = newOrder.ID,
itemID = item.itemID,
itemName = item.itemName,
quantity = item.quantity,
pricePerUnit = item.pricePerUnit,
totalPrice = item.total,
orderStatus = "PENDING"
};
DatabaseHelper.db.tblOrderDetails.InsertOnSubmit(newOrderDetail);
}
DatabaseHelper.db.SubmitChanges();
MessageBox.Show("Order placed!", "INFORMATION", MessageBoxButtons.OK, MessageBoxIcon.Information);
MessageBox.Show("Please save this document and/or print it and show it to the cashier.", "INFORMATION", MessageBoxButtons.OK, MessageBoxIcon.Information);
using (PrintForm frm = new PrintForm())
{
frm.PrintInvoice(newOrder.studentId,
fullName.Trim(),
newOrder.ID,
newOrder.orderDate.ToString("MM-dd-yyyy"),
subTotal,
cartList);
frm.ShowDialog();
}
ClearCart();
}
}
private void MStudentForm_Load(object sender, EventArgs e)
{
LabelStudentNum.Text = selectedStudent.StudentNumber.ToString();
if (selectedStudent.MiddleName.ToString().Length == 0)
{
fullName = selectedStudent.FirstName.ToString() + " " + selectedStudent.LastName.ToString();
}
else
{
fullName = selectedStudent.FirstName.ToString() + " " + selectedStudent.MiddleName.ToString() + " " + selectedStudent.LastName.ToString();
}
LabelName.Text = fullName.Trim();
LabelCourse.Text = selectedStudent.Course.ToString();
LabelGender.Text = selectedStudent.Gender.ToString();
switch (selectedStudent.Course.ToString())
{
case "BSIT":
courseCategory = "IT";
break;
case "BSHM":
courseCategory = "HM";
break;
case "BSTM":
courseCategory = "TM";
break;
case "BACOMM":
courseCategory = "AB";
break;
}
var allItems = from item in DatabaseHelper.db.tblItems
where item.category == courseCategory
|| item.category == "General"
|| item.gender == selectedStudent.Gender
select item;
foreach (var item in allItems)
{
tblItem item1 = new tblItem();
item1.ID = item.ID;
item1.itemName = item.itemName + " " + item.size;
item1.category = item.category;
item1.size = item.size;
item1.price = item.price;
item1.stocks = item.stocks;
if (item1.stocks > 0)
itemList.Add(item1);
else
notAvailableItemsList.Add(item1.itemName);
}
itemList = itemList.OrderBy(y => y.itemName).ToList();
notAvailableItemsList = notAvailableItemsList.OrderBy(y => y).ToList();
if(notAvailableItemsList.Count > 0)
{
string items = "";
foreach(string item in notAvailableItemsList)
{
items += item;
items += "\n";
}
MessageBox.Show("Not available items are:\n" + items, "INFORMATION", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}
foreach (var item in itemList)
{
CmbItems.Items.Add(item.itemName);
}
}
private void MStudentForm_FormClosing(object sender, FormClosingEventArgs e)
{
DialogResult dialogResult = MessageBox.Show("Are you sure you want to sign out?", "SIGN OUT", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (dialogResult == DialogResult.Yes)
{
this.Hide();
new LoginForm(false).Show();
}
else
{
e.Cancel = true;
}
}
private void DgvCartList_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
if (e.RowIndex >= 0)
{
string name = DgvCartList.Rows[e.RowIndex].Cells[0].Value.ToString();
int stockItem = 0;
foreach (var item in itemList)
{
if (name.Equals(item.itemName))
{
stockItem = item.stocks;
break;
}
}
if (DgvCartList.Rows[e.RowIndex].Cells[1].Value == null)
{
MessageBox.Show("You cannot leave this field empty.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
RefreshCartList();
return;
}
int quantity = int.Parse(DgvCartList.Rows[e.RowIndex].Cells[1].Value.ToString());
if (quantity > 99)
{
MessageBox.Show("You cannot add more than 99 items of the same type in cart.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
RefreshCartList();
return;
}
if (quantity > stockItem)
{
MessageBox.Show("You have reached the maximum number of stocks available.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning);
RefreshCartList();
return;
}
foreach (OrderDetail item in cartList)
{
if (item.itemName.Equals(name))
{
item.quantity = int.Parse(DgvCartList.Rows[e.RowIndex].Cells[1].Value.ToString());
RefreshCartList();
}
}
}
}
错误
System.Transactions Critical: 0 : <TraceRecord xmlns="http://schemas.microsoft.com/2004/10/E2ETraceEvent/TraceRecord" Severity="Critical"><TraceIdentifier>http://msdn.microsoft.com/TraceCodes/System/ActivityTracing/2004/07/Reliability/Exception/Unhandled</TraceIdentifier><Description>Unhandled exception</Description><AppDomain>ProwareSystem.exe</AppDomain><Exception><ExceptionType>System.ArgumentException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</ExceptionType><Message>Cannot bind to the property or column itemDescription on the DataSource.
Parameter name: dataMember</Message><StackTrace> at System.Windows.Forms.BindToObject.CheckBinding()
at System.Windows.Forms.BindToObject.SetBindingManagerBase(BindingManagerBase lManager)
at System.Windows.Forms.Binding.SetListManager(BindingManagerBase bindingManagerBase)
at System.Windows.Forms.ListManagerBindingsCollection.AddCore(Binding dataBinding)
at System.Windows.Forms.BindingsCollection.Add(Binding binding)
at System.Windows.Forms.BindingContext.UpdateBinding(BindingContext newBindingContext, Binding binding)
at System.Windows.Forms.Control.UpdateBindings()
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.ListControl.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnParentBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.set_BindingContextInternal(BindingContext value)
at System.Windows.Forms.ContainerControl.set_BindingContext(BindingContext value)
at System.Windows.Forms.ContainerControl.get_BindingContext()
at System.Windows.Forms.Control.get_BindingContextInternal()
at System.Windows.Forms.Control.get_BindingContext()
at System.Windows.Forms.Control.UpdateBindings()
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.ListControl.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnParentBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.ContainerControl.OnCreateControl()
at System.Windows.Forms.Form.OnCreateControl()
at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
at System.Windows.Forms.Control.CreateControl()
at System.Windows.Forms.Control.WmShowWindow(Message&amp; m)
at System.Windows.Forms.Control.WndProc(Message&amp; m)
at System.Windows.Forms.ScrollableControl.WndProc(Message&amp; m)
at System.Windows.Forms.Form.WmShowWindow(Message&amp; m)
at System.Windows.Forms.Form.WndProc(Message&amp; m)
at MaterialSkin.Controls.MaterialForm.WndProc(Message&amp; m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message&amp; m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message&amp; m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)</StackTrace><ExceptionString>System.ArgumentException: Cannot bind to the property or column itemDescription on the DataSource.
Parameter name: dataMember
at System.Windows.Forms.BindToObject.CheckBinding()
at System.Windows.Forms.BindToObject.SetBindingManagerBase(BindingManagerBase lManager)
at System.Windows.Forms.Binding.SetListManager(BindingManagerBase bindingManagerBase)
at System.Windows.Forms.ListManagerBindingsCollection.AddCore(Binding dataBinding)
at System.Windows.Forms.BindingsCollection.Add(Binding binding)
at System.Windows.Forms.BindingContext.UpdateBinding(BindingContext newBindingContext, Binding binding)
at System.Windows.Forms.Control.UpdateBindings()
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.ListControl.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnParentBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.set_BindingContextInternal(BindingContext value)
at System.Windows.Forms.ContainerControl.set_BindingContext(BindingContext value)
at System.Windows.Forms.ContainerControl.get_BindingContext()
at System.Windows.Forms.Control.get_BindingContextInternal()
at System.Windows.Forms.Control.get_BindingContext()
at System.Windows.Forms.Control.UpdateBindings()
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.ListControl.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnParentBindingContextChanged(EventArgs e)
at System.Windows.Forms.Control.OnBindingContextChanged(EventArgs e)
at System.Windows.Forms.ContainerControl.OnCreateControl()
at System.Windows.Forms.Form.OnCreateControl()
at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
at System.Windows.Forms.Control.CreateControl()
at System.Windows.Forms.Control.WmShowWindow(Message&amp; m)
at System.Windows.Forms.Control.WndProc(Message&amp; m)
at System.Windows.Forms.ScrollableControl.WndProc(Message&amp; m)
at System.Windows.Forms.Form.WmShowWindow(Message&amp; m)
at System.Windows.Forms.Form.WndProc(Message&amp; m)
at MaterialSkin.Controls.MaterialForm.WndProc(Message&amp; m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message&amp; m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message&amp; m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)</ExceptionString></Exception></TraceRecord>
An unhandled exception of type 'System.ArgumentException' occurred in System.Windows.Forms.dll
Cannot bind to the property or column itemDescription on the DataSource.
【问题讨论】：
-
错误消息很清楚，您实际上自己回答了这个问题：检查所有文件 - 特别是 XAML 文件 - 仍然应该有一个“itemDescription”需要重命名为“itemName”。您应该真正考虑一下您的表定义，并使其尽可能保持不变，以避免将来出现这种工作量。附言这种问题可能更适合 Stackexchanges 的代码审查
-
我使用 linq to sql DBML 文件，但找不到这样的东西。我认为当我尝试刷新它时它会自动更新，但似乎我找不到错误在哪里。
标签： c# .net windows forms winforms