将DataGridView中的ComboBox的值匹配到另一个单元格

Question

I have a DataGridView with a ComboBox column. The ComboBox gets filled with a specific list of names and they are identical for every row in the DataGridView .

After I fill my DataGridView , I would like to do the following:

I want every Combo's value to be set to the corresponding row's “Table Columns” value, if exists.

Ie in the picture above I want the value of the first Combo to be “id” (if it contains an item named “id”), the second to be “firstname”, etc.

If the value is not found, it should not select any value in the ComboBox .

Update : My current code that is not working

private void Mappings_Load(object sender, EventArgs e)
{       
    dgv.DataSource = tableColumns.Select(x => new { Value = x }).ToList();
    dgv.Columns[0].HeaderText = "Table Columns";
    DataGridViewComboBoxColumn comboColumn = new DataGridViewComboBoxColumn();
    comboColumn.HeaderText = "File Columns";
    foreach (var item in fileColumns)
        comboColumn.Items.Add(item);
    dgv.Columns.Add(comboColumn);
    foreach(DataGridViewRow row in dgv.Rows)
    {
        string tableColumnValue = row.Cells[0].Value.ToString();
        row.Cells[0].Value = tableColumnValue;           
    }
}

Answer 1

A while ago I did a similar thing:

1. Recognize which fields are of type enum
2. For the fiels of type enum , show a ComboBox in the cell of the DataGridView (containing all the possible values of the enum ) instead of the simple text field.

I think you only need to change certain parts of the code to transform it to what you are trying to achieve:

public partial class TableView<CollectionType, ItemType> : Form
{

    public TableView(CollectionType elements)
    {

        InitializeComponent();

        // custom:
        this.DataGridView.DataSource = elements;
        AdaptColumnsToColumnValueType();

    }

    private void AdaptColumnsToColumnValueType()
    {
        for (int columnIndex = 0; columnIndex < this.DataGridView.Columns.Count; columnIndex++)
        {
            var column = (DataGridViewColumn)this.DataGridView.Columns[columnIndex];
            if (column.ValueType.IsEnum)
            {
                ReplaceColumnInDatagridView(
                    oldColumn: column,
                    newColumn: CreateComboBoxWithEnums(column));
            }
        }
    }

    private void ReplaceColumnInDatagridView(DataGridViewColumn oldColumn, DataGridViewColumn newColumn)
    {
        int columnIndex = oldColumn.Index;
        this.DataGridView.Columns.Remove(oldColumn);
        this.DataGridView.Columns.Insert(columnIndex, newColumn);
    }

    private DataGridViewComboBoxColumn CreateComboBoxWithEnums(DataGridViewColumn replacedEnumColumn)
    {
        var comboboxColumn = new DataGridViewComboBoxColumn();
        comboboxColumn.DataSource = Enum.GetValues(replacedEnumColumn.ValueType);
        comboboxColumn.DataPropertyName = replacedEnumColumn.DataPropertyName;
        comboboxColumn.Name = replacedEnumColumn.Name;
        return comboboxColumn;
    }

}

Answer 2

you can use the DataGridViews RowsAdded event.

Edit: cmb is your ComboBoxColumn

private void dataGridView1_RowsAdded(object sender, DataGridViewRowsAddedEventArgs e) {
   //Check if comboboxcolumn contains the value                
   if(cmb.Items.Contains(dataGridView1.Rows[e.RowIndex].Cells[0].Value)) {
   //Set the value
     dataGridView1.Rows[e.RowIndex].Cells["cmb"].Value = dataGridView1.Rows[e.RowIndex].Cells[0].Value;
         }
    }

Answer 3

Trace the change .. you almost did it

    private void Form1_Load(object sender, EventArgs e)
    {
        string[] tableColumns = new string[] { "A", "B", "C", "D" };

        string[] fileColumns = new string[] { "A", "B", "C", "X" };

        dgv.DataSource = tableColumns.Select(x => new { Value = x }).ToList();

        dgv.Columns[0].HeaderText = "Table Columns";
        DataGridViewComboBoxColumn comboColumn = new DataGridViewComboBoxColumn();
        comboColumn.HeaderText = "File Columns";
        foreach (var item in fileColumns)
            comboColumn.Items.Add(item);
        dgv.Columns.Add(comboColumn);

        foreach (DataGridViewRow row in dgv.Rows)
        {
            string tableColumnValue = row.Cells[0].Value.ToString();

            //Change is here
            if (fileColumns.Any(i => i == tableColumnValue))
            {
                row.Cells[1].Value = tableColumnValue;
            }
            //end change
        }
    }