You're missing the key feature from WPF data processing. You're not actually accessing items in a grid like rows and columns in an Excel sheet. You should think of it as accessing objects in an ObservableCollection<T> and its properties.
Say you have a class like this:
| public class Person |
| { |
| public string FirstName { get ; set ;} |
| public string LastName { get ; set ;} |
| } |
And you populate your grid like so:
| grid.ItemSource = new ObservableCollection<Person> { |
| new Person { FirstName = "John" , LastName = "Doe" }, |
| new Person { FirstName = "Jane" , LastName = "Eod" } |
| } |
Instead of accessing a first column you access the property. Something like so:
| var person = grid .SelectedItem as Person; |
| if (person != null) textBlock.Text = person .FirstName; |
Bigsby, Lisboa, Portugal
That seems as a good solution to the problem, but how do I do this if I'm making a three layer application. Layer:
1. DataAcces (this has the Linq to Sql class)
2. BusinessLogic (has classes to tables, linq queries etc.)
3. User Interface (UI)
So I have the DataGrid on the UI and it's populated like this:
// Loading initial data into the DataGrids
clsLoans objLoans = new clsLoans();
dgUserSearch.ItemsSource = objLoans.GetAllUsers();
The GetAllUsers() function is called from the BL and is in a class called clsLoans, and returns an IQueriable LINQ query.
public SmalLibData myDb = new SmalLibData(ConfigurationManager.ConnectionStrings["MyConnString"].ConnectionString);
public IQueryable GetAllUsers()
{
return from us in myDb.User
from usst in myDb.UserStatus
where us.UserStatusID == usst.UserStatusID
select new
{
us.UserID,
us.UserName,
usst.UserStatusDef,
us.Address,
us.MothersName
};
}
I also have a class in the BL for each table with the functions and queries related to it. For example the class for the User table (clsUser) looks like this:
public class clsUserBL
{
public SmalLibData myDb = new SmalLibData(ConfigurationManager.ConnectionStrings["MyConnString"].ConnectionString);
#region Private
private int mUserID;
private string mUserName;
private string mMothersName;
private string mAddress;
private clsUserStatusBL mUserStatus = new clsUserStatusBL();
#endregion
#region Properties
public int UserID
{
get { return mUserID; }
set { mUserID = value; }
}
public string UserName
{
get { return mUserName; }
set { mUserName = value; }
}
public string MothersName
{
get { return mMothersName; }
set { mMothersName = value; }
}
public string Address
{
get { return mAddress; }
set { mAddress = value; }
}
public clsUserStatusBL UserStatus
{
get { return mUserStatus; }
set { mUserStatus = value; }
}
#endregion
public IQueryable GetAllUsers()
{
return from c in myDb.User
from us in myDb.UserStatus
where c.UserStatusID == us.UserStatusID
//join us in objUserDal.GetUserStatus() on c.UserStatusID equals us.UserStatusID
select new
{
UserID = c.UserID,
UserName = c.UserName,
MothersName = c.MothersName,
Address = c.Address,
UserStatusDef = us.UserStatusDef
};
}
public Boolean Reccord(string _Action)
{
User user = new User();
Boolean Success = true;
switch (_Action)
{
case "Insert":
user.UserName = mUserName;
user.MothersName = mMothersName;
user.Address = mAddress;
user.UserStatusID = mUserStatus.UserStatusID;
myDb.User.InsertOnSubmit(user);
break;
case "Update":
user = myDb.User.Where(c => c.UserID == mUserID).First<User>();
user.UserName = mUserName;
user.MothersName = mMothersName;
user.Address = mAddress;
user.UserStatusID = mUserStatus.UserStatusID;
break;
case "Delete":
user = myDb.User.Where(c => c.UserID == mUserID).First<User>();
myDb.User.DeleteOnSubmit(user);
break;
}
try
{
// Submit changes to the database. Executes the Insert, Update, or Delete query.
myDb.SubmitChanges();
Success = true;
}
catch (ChangeConflictException)
{
// Resolving conflicts
Success = false;
myDb.ChangeConflicts.ResolveAll(RefreshMode.KeepChanges);
}
return Success;
}
The question now is, what steps to take in order to retrieve a single cells value from the selected row in the wpf datagrid?
I tried to implement the method mentioned above, but somehow wasn't succesfull. Can somebody please point me in the right direction...
