C# DataGridView - 由數據源引起的單元格更改的事件

Question

由於 DataSource 的變化，DataGridView 中的單元格值是否發生變化？

我創建了自己的自定義類來實現 INotifyPropertyChanged，

public class CustomWorkbook : INotifyPropertyChanged
{
    string filepath;
    string status;
    public event PropertyChangedEventHandler PropertyChanged;

    private void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    ...
}

並將其綁定到我的 DataGridView 如下，

BindingList<CustomWorkbook> workbookList = new BindingList<CustomWorkbook>();
BindingSource workbookBinding = new BindingSource(workbookList , null);
dataGridViewWorkbooks.DataSource = workbookBinding;

目前，單元格值會根據需要自動更新，但我想添加更多處理和美學效果，這些效果需要知道單元格值何時發生變化以及哪個單元格（即使更新的單元格變為綠色，待處理的單元格變為黃色）

我已經在 DataGridView 中嘗試了 CellValueChanged 事件，但這似乎只適用於用戶編輯。 NotifyPropertyChanged 事件將在值發生更改時觸發……但它不會提供對已更改單元格的任何引用。

Answer 1

在采取了僅向大多數DataGridView事件添加事件處理程序的蠻力方法后，我發現DataBindingComplete事件正是我所追求的。 每當我的CustomWorkbook類中的屬性發生更改時，都會引發此事件（我假設INotifyPropertyChanged逐漸傳輸到BindingList 、 BindingSource ，最后是DataGridView DataSource ？）。

雖然此事件不提供對已更改屬性的相應單元格的任何引用，但我最終只是遍歷所有單元格，因為我知道包含相關單元格的列的名稱。

    /// <summary>
    /// Called whenever changes have been made to the binded list
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void DataGridViews_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e)
    {
        DataGridViews_UpdateStatusColour(sender as DataGridView);
    }

    /// <summary>
    /// Change the colour of the cells in the column whose DataPropertyName is "Status"
    /// </summary>
    /// <param name="grid"></param>
    private void DataGridViews_UpdateStatusColour(DataGridView grid)
    {
        // Get the column index
        int targetColumn = 0;
        foreach (DataGridViewColumn col in grid.Columns)
        {
            if (col.DataPropertyName == "Status")
            {
                targetColumn = col.Index;
                break;
            }
        }

        // Loop through every row, and colour the corresponding cell
        foreach (DataGridViewRow row in grid.Rows)
        {
            DataGridViewCell cell = row.Cells[targetColumn];
            switch (cell.Value.toString())
            {
                case ("UPDATED"):
                    cell.Style.BackColor = System.Drawing.Color.Green;
                    cell.Style.SelectionBackColor = System.Drawing.Color.Green;
                    break;
                case ("PENDING"):
                    cell.Style.BackColor = System.Drawing.Color.Orange;
                    cell.Style.SelectionBackColor = System.Drawing.Color.Orange;
                    break;
                case ("MISSING"):
                    cell.Style.BackColor = System.Drawing.Color.LightSalmon;
                    cell.Style.SelectionBackColor = System.Drawing.Color.LightSalmon;
                    break;
                case ("ERROR"):
                    cell.Style.BackColor = System.Drawing.Color.Red;
                    cell.Style.SelectionBackColor = System.Drawing.Color.Red;
                    break;
                default:
                    break;
            }
        }
    }

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