你试过文本属性了吗?这对我很管用。

ComboBox1.Text = "test1";

SelectedText属性用于组合框的文本框部分中可编辑文本的选定部分。

  ListItem li = DropDownList.Items.FindByValue("13001");
  DropDownList.SelectedIndex = ddlCostCenter.Items.IndexOf(li);

你的案子可以用

DropDownList.Items.FindByText("Text");

在组合框中找到mySecondObject (MyObject类型)(包含MyObjects列表)并选择该项:

foreach (MyObject item in comboBox.Items)
{
   if (item.NameOrID == mySecondObject.NameOrID)
    {
        comboBox.SelectedItem = item;
        break;
    }
}

SelectedText用于在字符串编辑器中获取或设置组合框中所选项目的实际文本。如果你设置了:

comboBox1.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;

Use:

comboBox1.SelectedItem = "test1";

or:

comboBox1.SelectedIndex = comboBox1.Items.IndexOf("test1");

我已经创建了一个函数，它将返回值的索引

        public static int SelectByValue(ComboBox comboBox, string value)
        {
            int i = 0;
            for (i = 0; i <= comboBox.Items.Count - 1; i++)
            {
                DataRowView cb;
                cb = (DataRowView)comboBox.Items[i];
                if (cb.Row.ItemArray[0].ToString() == value)// Change the 0 index if your want to Select by Text as 1 Index
                {
                    return i;
                }
            }
            return -1;
        }

这个方案是基于MSDN的，我做了一些修改。

It finds exact or PART of string and sets it. private int lastMatch = 0; private void textBoxSearch_TextChanged(object sender, EventArgs e) { // Set our intial index variable to -1. int x = 0; string match = textBoxSearch.Text; // If the search string is empty set to begining of textBox if (textBoxSearch.Text.Length != 0) { bool found = true; while (found) { if (comboBoxSelect.Items.Count == x) { comboBoxSelect.SelectedIndex = lastMatch; found = false; } else { comboBoxSelect.SelectedIndex = x; match = comboBoxSelect.SelectedValue.ToString(); if (match.Contains(textBoxSearch.Text)) { lastMatch = x; found = false; } x++; } } } else comboBoxSelect.SelectedIndex = 0; }

希望我能帮上忙!