dotnet/wpf · error · InvalidOperationException

SR.DataGrid_AutomationInvokeFailed

Error message

SR.DataGrid_AutomationInvokeFailed

What it means

DataGridCellItemAutomationPeer.Invoke implements IInvokeProvider.Invoke for a DataGrid cell. It attempts to invoke/activate the cell (and for NewItemPlaceholder rows, create a new item). If the invoke did not succeed and the cell is not a NewItemPlaceholder, the peer throws InvalidOperationException with SR.DataGrid_AutomationInvokeFailed, meaning the cell could not be programmatically activated.

Solutions

  1. Ensure the target column/cell is editable (DataGridColumn.IsReadOnly == false and DataGrid.IsReadOnly == false) before invoking.
  2. Handle InvalidOperationException from Invoke and fall back to selection (ISelectionItemProvider.Select) instead of invocation.
  3. Do not call Invoke on NewItemPlaceholder rows; detect the placeholder via Item and skip it.
  4. Verify the DataGrid is loaded, realized, and the cell is in view before invoking from an automation client.

Example fix

// before (automation client)
var invoke = (IInvokeProvider)cellPattern;
invoke.Invoke(); // throws on non-editable cell

// after
if (column.IsReadOnly) { selection.Select(); } else { invoke.Invoke(); }
Defensive patterns

Strategy: try-catch

Validate before calling

if (dataGrid.IsReadOnly || column.IsReadOnly) { /* skip Invoke */ }

Type guard

bool IsInvocable(DataGridCellItemAutomationPeer peer) => peer?.OwningDataGrid != null && !peer.OwningDataGrid.IsReadOnly;

Try / catch

try { ((IInvokeProvider)peer).Invoke(); } catch (InvalidOperationException ex) { /* fall back to Select */ }

Prevention

When it happens

Trigger: Calling Invoke() via UI Automation (IInvokeProvider) on a DataGrid cell whose OwningDataGrid.BeginEdit/activation path fails — e.g. the cell cannot enter edit mode, the DataGrid is not editable, or the underlying item cannot be activated — while the cell is not a NewItemPlaceholder row.

Common situations: UI Automation tests or screen readers invoking a read-only cell; invoking cells in a DataGrid whose columns are all read-only or whose IsReadOnly is true; invoking a cell in a templated/custom row where activation fails; automation scripts against DataGrids expecting rows (not cells) to be invocable.

Understand the failure class

Background: UnsupportedOperationException and "is not supported" errors: when a library deliberately refuses a call — this error's family across 30 libraries.

Related errors

AI-assisted analysis of dotnet/wpf@81131a70a4 (2026-09-14). Data as JSON: /api/errors/60b91b5ad6f50d91. Report an issue: GitHub.

Appendix: source

Thrown at src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Automation/Peers/DataGridCellItemAutomationPeer.cs:650

                    // other cells may need to be de-selected, let the DataGrid handle that.
                    this.OwningDataGrid.HandleSelectionForCellInput(cell, /* startDragging = */ false, /* allowsExtendSelect = */ false, /* allowsMinimalSelect = */ false);

                    // the cell is now the datagrid's "current" cell, so BeginEdit will put
                    // it into edit mode
                    success = this.OwningDataGrid.BeginEdit();
                }
                else
                {
                    success = true;
                }
            }

            // Invoke on a NewItemPlaceholder row creates a new item.
            // BeginEdit on a NewItemPlaceholder row returns false.
            if (!success  && !IsNewItemPlaceholder)
            {
                throw new InvalidOperationException(SR.DataGrid_AutomationInvokeFailed);
            }
        }

        #endregion

        #region IScrollItemProvider

        void IScrollItemProvider.ScrollIntoView()
        {
            this.OwningDataGrid.ScrollIntoView(Item, _column);
        }

        #endregion

        #region ISelectionItemProvider

        bool ISelectionItemProvider.IsSelected
        {

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