在DataGridView Winform中执行文本框自动完成时出错

Question

我在为specified cast is not valid尝试autocomplete时遇到此错误datagridviewtextboxcell。我附上了代码的快照以及stack trace。我错过了什么吗？

private void dataGridView1_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e)
    {
        TextBox prodCode = e.Control as TextBox;
        if (dataGridView1.CurrentCell.ColumnIndex == 0)
        {
            var source = new AutoCompleteStringCollection();
            String[] stringArray = newDB.CustomerTbls.Where(s => s.Status == "Active" & s.Type == "Customer").Select(s => s.Name).ToArray<string>();
            source.AddRange(stringArray);

            if (prodCode != null)
            {
                prodCode.AutoCompleteMode = AutoCompleteMode.SuggestAppend;
                prodCode.AutoCompleteCustomSource = source;
                prodCode.AutoCompleteSource = AutoCompleteSource.CustomSource;

            }
        }
        else
            prodCode.AutoCompleteCustomSource = null;
    }

Answer 1

正如此线程Problem faced in AutoComplete code for TextBox 中的decyclone所建议的，在新解决方案中创建一个新的Windows应用程序项目，创建一个新表单并使用该表单尝试以下代码，即创建一个String[]的DataTable行计数的大小，然后将其添加到AutoCompleteStringCollection对象

AutoCompleteStringCollection data = new AutoCompleteStringCollection ();
data.AddRange(new string[]
   {
      "January",
      "February",
      "March",
      "April",
      "May",
      "June",
      "July",
      "August",
      "September",
      "October",
      "November",
      "December"
   });

// Create and initialize the text box
var prodCode = new TextBox
{
   AutoCompleteCustomSource = data,
   AutoCompleteMode = AutoCompleteMode.SuggestAppend,
   AutoCompleteSource = AutoCompleteSource.CustomSource,
   Location = new Point(20, 20),
   Width = ClientRectangle.Width - 40,
   Visible = true
};

看看它是否有效。如果它不起作用，那么您可以尝试本文AutoCompleteCustomSource – Specified Cast is Not Valid 中概述的替代解决方案，即将TextBox替换为ComboBox并将其DropDownStyle设置为{{ 1}}。

Answer 2

我自己想出了这个问题。我尝试Datagridview Autocomplete的形式是Child Form。我上面发布的代码是new Form。所以我打开了Child Form作为一个新的Thread，并尝试运行代码，它工作了!! Thanx为你所有的帮助@chridam。