ADO.NET :: How To Delete Associated Entity
Mar 1, 2011
I have a project with EF4 e poco templated entity. I need to delete a User entity that is associated via foreign key referential constraint to UsersinRoles and Profile entities in this way:
User 1:1 Profile
User 1:many UsersinRoles
On msdn I've found that: "When a primary key of the principal entity is part of the primary key of the dependent entity, then deleting the principal object also deletes all the loaded dependent objects. This is the same as defining the cascading delete rules on the relationship" So I can guess that deleting the User entity will delete the other two entities as well. so I call the delete method on user entity:
[Code]....
and the Usersinroles entities are deleted correctly instead of Profile that lives as an orphan in the db. what can I check to make it work correctly?
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Jan 5, 2011
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Dec 27, 2010
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[Code]....
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Mar 10, 2010
i have 2 tables without any cascade deletind. i wont to delete parent object with all child objects. i do like this
//get parent object
return _dataContext.Menu.Include("ChildMenu").Include("ParentMenu").Include("Pictures").FirstOrDefault(m => m.MenuId == id);
//then i loop all child objects
var picList = (List<Picture>)menu.Pictures.ToList();
//foreach (var item in menu.Pictures)
for (int i = 0; i < picList.Count; i++)
{
if (File.Exists(HttpContext.Current.Server.MapPath(picList[i].ImgPath)))
{
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}
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{
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}
//**what must i do here?**
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//menu.Pictures.de
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_dataContext.DeleteObject(_dataContext.Menu.Include("ChildMenu").Include("ParentMenu").Include("Pictures").FirstOrDefault(m => m.MenuId == id););
_dataContext.SaveChanges();
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Apr 30, 2010
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Feb 8, 2011
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[Code]....
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Jan 4, 2011
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Feb 1, 2010
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[Code]....
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Feb 9, 2011
I get an cast exception when i am trying to insert an entity in Entity Framework (using code-first). From this code :
public virtual T Insert(T entity)
{
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}................................
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Feb 10, 2011
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[Code]....
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Mar 31, 2011
I have a stupid problem with the Entity Framework. I get the following Exception:
[Code]....
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[Code]....
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Sep 24, 2010
I am trying to do something like this:
[Code]....
But ofcourse it is not working as I want to. The Ordering works on Question.Order, but I would also the
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Nov 18, 2010
How do I reference the delete button to add the delete confirmation box when I have both the Edit and Delete buttons as the last two columns in the Gridview control. The following code works fine without any issues when I have the delete button only:
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType != DataControlRowType.DataRow) return;
int lastCellIndex = e.Row.Cells.Count - 1;
Button db = (Button)e.Row.Cells[lastCellIndex].Controls[0];
db.OnClientClick = "if (!window.confirm('Are you sure you want to delete this record?')) return false;";
}
But, when I have both the Edit and the Delete buttons, I get the following error when I click the edit button while the delete button works fine.
Specified argument was out of the range of valid values. Parameter name: index
How do I reference the delete button so the edit button is not affected in this case?
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Feb 3, 2010
Using "Enable Delete" from Gridview control, I can delete (besides, update, sort, paging, etc) data from the database (this is done automatically). However, how can I delete the actual image that resides in my image folder (i.e. from "pix" folder )? What is the best way to delete image? If using code behind, how? Please write a full code for me. Here is my source code.
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="photoID"
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Nov 7, 2011
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Feb 8, 2010
I have a grid contol that allows delete what I would like to have is someway to say Are you sure you want to delete?I found this code online, and tried it but it did not work, Do I need something more some behind code maybe?Here is what I found online:Adding 'Delete Protection' to controls If you use a control set up to allow Delete, the Delete button gives a straight delete without any warning, which can be dangerous.To give a warning dialog box, add an OnClientClick event to the Delete button, as follows.
<asp:LinkButton
ID="DeleteButton"
runat="server" CausesValidation="False"
CommandName="Delete"
OnClientClick="return confirm('Are you sure you want to delete this record?');"
Text="Delete">
</asp:LinkButton>
Here is my code: You can see where I added the code from above.
<ItemTemplate>
ID:<asp:label id="IDLabel" runat="server" Text='<%# Eval("ID") %>' /><br />
Name:<asp:label id="NameLabel" runat="server" Text='<%# Bind("Name") %>' /><br />
Destination:<asp:label id="DestinationLabel" runat="server" Text='<%# Bind("Destination") %>' /><br />
OutDate:<asp:label id="OutDateLabel" runat="server" Text='<%# Bind("OutDate") %>' /><br />
ReturnDate:<asp:label id="ReturnDateLabel" runat="server" Text='<%# Bind("ReturnDate") %>' /><br />
LeaveTime:<asp:label id="LeaveTimeLabel" runat="server" Text='<%# Bind("LeaveTime") %>' /><br />
ReturnTime:<asp:label id="ReturnTimeLabel" runat="server" Text='<%# Bind("ReturnTime") %>' /><br />
ContactNumber:<asp:label id="ContactNumberLabel" runat="server" Text='<%# Bind("ContactNumber") %>' />
<asp:linkbutton id="EditButton" runat="server" CausesValidation="False" CommandName="Edit" Text="Edit" />
<asp:linkbutton id="DeleteButton" runat="server" CausesValidation="False" CommandName="Delete" OnClientClick="return confirm('Are you sure you want to delete this record?');" Text="Delete" />
<asp:linkbutton id="NewButton" runat="server" CausesValidation="False" CommandName="New" Text="New" />
</ItemTemplate>
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