将不同条目从数据源绑定到 DataGridViewComboBoxCell

Question

我想在 DataGridView 中显示以下数据：

DataEntry[] data = new[]{
        new DataEntry(){Name = "A", Entries = new []{ "1", "2"}},
        new DataEntry(){Name = "B", Entries = new []{ "1", "2", "3"}}};

“名称”将是一个简单的文本框字段，“条目”将是一个组合框，其中可供选择的项目是列表中的元素。

所以在这个例子中会有 2 行（下面是 datagridview 的样子）：

       Name                         Entries

Row1 :    A                    <choice of "1" or "2">
Row1 :    B                    <choice of "1" or "2" or "3">

我的问题是，我如何绑定这些数据？！我查看了 DataPropertyName、DisplayMember 和 ValueMember 属性...但无法解决这个问题。

下面是当前的代码 - 带有注释，我需要在其中添加神奇的几行来为 Entries 列设置 DataSource 等。

public partial class Form1 : Form
    {
        DataEntry[] data = new[]{
            new DataEntry(){Name = "A", Entries = new []{ "1", "2"}},
            new DataEntry(){Name = "B", Entries = new []{ "1", "2", "3"}}};

        public Form1()
        {
            InitializeComponent();
            dataGridView1.AutoGenerateColumns = false;

            var nameCol = new DataGridViewTextBoxColumn();
            nameCol.DataPropertyName = "Name";

            var entriesCol = new DataGridViewComboBoxColumn();

                    //entriesCol. ???? = "Entries"; !!

            dataGridView1.Columns.AddRange(new DataGridViewColumn[] { nameCol, entriesCol });

            dataGridView1.DataSource = data;   
        }
    }


    public class DataEntry
    {
        public string Name { get; set; }
        public IEnumerable<string> Entries { get; set; }
    }

Answer 1

今天早上过来，10 分钟内我就搞定了！

感谢this MSDN forum post

解决方案是订阅“DataBindingComplete”事件，然后遍历每一行并在每个 ComboBoxCell 上设置数据源。有一个更优雅的解决方案会很好 - 但是嘿 - 它有效！

以下是我在原始问题中提交的代码示例的工作版本：

public partial class Form1 : Form
{
    DataEntry[] data = new[]{
        new DataEntry(){Name = "A", Entries = new []{ "1", "2", "3", "4"}},
        new DataEntry(){Name = "B", Entries = new []{ "1", "2", "3"}}};


    string[] cols = new[] { "col1", "col2" };

    public Form1()
    {
        InitializeComponent();

        dataGridView1.AutoGenerateColumns = false;

        var nameCol = new DataGridViewTextBoxColumn();
        nameCol.DataPropertyName = "Name";

        var entriesCol = new DataGridViewComboBoxColumn();
        entriesCol.Name = "Entries";
        dataGridView1.Columns.AddRange(new DataGridViewColumn[] { nameCol, entriesCol });

        dataGridView1.DataSource = data;
        dataGridView1.DataBindingComplete += new DataGridViewBindingCompleteEventHandler(dataGridView1_DataBindingComplete);
    }

    void dataGridView1_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e)
    {
        for (int i = 0; i < dataGridView1.Rows.Count; i++)
        {
            DataGridViewComboBoxCell comboCell = (DataGridViewComboBoxCell)dataGridView1.Rows[i].Cells["Entries"];
            DataEntry entry = dataGridView1.Rows[i].DataBoundItem as DataEntry;

            comboCell.DataSource = entry.Entries;
            comboCell.Value = entry.Entries.First();
        }
    }
}

public class DataEntry
{
    public string Name { get; set; }
    public IEnumerable<string> Entries { get; set; }
}

Answer 2

我最近不得不这样做并找到了不同的解决方案。

我使用了 2 个 BindingSource 来完成工作。第一个用于填充 Datagrid，第二个用于 ComboBoxColumn 并使用第一个 BindingSource，因为它的 DataSource 引用了它的 DataMember。

这是我们可能要绑定的 DataObject：

class DataObject
{
    public string Name { get; set; }
    public string Value { get; set; }
    public string [] ValueList { get; set; }
}

Designer 文件如下所示：

// dataGridView1
this.dataGridView1.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
  this.nameDataGridViewTextBoxColumn,
  this.valueDataGridViewTextBoxColumn});
this.dataGridView1.DataSource = this.bindingSource1;
// bindingSource1
this.bindingSource1.DataSource = typeof(SomeNamespace.DataObject);
// valueListBindingSource
this.valueListBindingSource.DataMember = "ValueList";
this.valueListBindingSource.DataSource = this.bindingSource1;
// nameDataGridViewTextBoxColumn
this.nameDataGridViewTextBoxColumn.DataPropertyName = "Name";
// valueDataGridViewTextBoxColumn
this.valueDataGridViewTextBoxColumn.DataPropertyName = "Value";
this.valueDataGridViewTextBoxColumn.DataSource = this.valueListBindingSource;

那么一个简单的表单可能如下所示：

public Form1 ()
{
  InitializeComponent ();
  m_objects = new List<DataObject> {
    new DataObject { Name = "foo", ValueList = new [] { "1", "2", "3", "4" }},
    new DataObject { Name = "bar", ValueList = new [] { "a", "b", "c" }}
  };
  bindingSource1.DataSource = m_objects;
}
private IList<DataObject> m_objects;