Datagrid error when casting to model only when isReadOnly is false?-CodePudding

I have Datagrid and I want to cast the data from each row to a specific model. the casting code is

        private List<SearchAndReplaceModel> getSelectedWordes()
        {
           DGKeywords.UnselectAllCells();
           var repo = new SearchAndReplaceRepository();
          List<SearchAndReplaceModel> selectedWordes = new List<SearchAndReplaceModel>();
           List<SearchAndReplaceModel> dataFromGrid=DGKeywords.Items.Cast<SearchAndReplaceModel>().ToList();
           if (dataFromGrid != null)
            for (int i = 0; i < dataFromGrid.Count; i  )
            {
                selectedWordes.Add ( dataFromGrid[i]);
            }
           return selectedWordes;
        }

the stranger thing is that the code is working perfectly when the property of Datagrid isReadOnly=true but there is exception when I change it to isReadOnly=false

the exception :

Exception thrown: 'System.InvalidCastException' in System.Core.dll An exception of type 'System.InvalidCastException' occurred in System.Core.dll but was not handled in user code Unable to cast object of type 'MS.Internal.NamedObject'

CodePudding user response：

use .OfType() extension method instead of .Cast():

private List<SearchAndReplaceModel> getSelectedWordes()
{
   DGKeywords.UnselectAllCells();
   return DGKeywords.Items.OfType<SearchAndReplaceModel>().ToList();
}

or it maybe simpler to iterate DGKeywords.ItemsSource (depending on how DataGrid is filled with data)