輸入檢查其列表中項目的自動完成組合框

Question

有沒有一種方法可以檢查何時在comboBox中輸入了一個項目，列表中實際上只有一個項目？ 為了進一步說明，如果選擇了列表之外的任何內容，它將不接受該輸入。 我查看了stackoverflow，但是唯一的解決方案是將comboBox樣式更改為下拉列表樣式。 這樣做的問題在於，有一百多條記錄可供選擇，因此comboBox上的自動完成功能對於通過輸入的用戶輸入將其過濾掉是絕對必要的。

更新（聲明全局匹配）：

private void comboBox3_TextChanged(object sender, EventArgs e)
    {
        ComboBox c = ((ComboBox)sender);
        string[] items = c.Items.OfType<string>().ToArray();
        matched = items.Any(i => i == c.Text.Trim().ToLower());

    }

這是執行的地方：

 private void button5_Click(object sender, EventArgs e)
    {

        if (matched==false)
        {
            MessageBox.Show("Value in Carimed Items does not exist");
        }else
        {


            if (string.IsNullOrEmpty(comboBox5.Text))
        {
            MessageBox.Show("Please select output file to be written to!");
        }
        else
        {

            //  int current = 0;
            if (comboBox1.Text.Trim() == string.Empty)
            {
                MessageBox.Show("All fields must be filled in before saving!");

            }
            else
            {


                    //  StringBuilder csvconten = new StringBuilder();
                    // csvconten.AppendFormat("{0},{1},{2},{3},{4},{5}\r\n", comboBox2.Text, textBox5.Text, textBox2.Text, comboBox3.Text, textBox3.Text, comboBox1.Text);
                    // string csvpath = "cross_check.csv";
                    // File.AppendAllText(csvpath, csvconten.ToString());

                    string connectionString3 = "Data Source=LPMSW09000012JD\\SQLEXPRESS;Initial Catalog=Pharmacy_Output_File;Integrated Security=True";
                    string query3 = "INSERT INTO dbo.[" + comboBox5.Text + "] VALUES('" + comboBox2.Text + "','" + textBox5.Text.Replace("'", "''") + "','" + textBox7.Text.Replace("'", "''") + "','" + textBox2.Text.Replace("'", "''") + "','" + comboBox3.Text.Replace("'", "''") + "','" + textBox3.Text + "','" + comboBox1.Text + "');";

                    using (SqlConnection connection = new SqlConnection(connectionString3))
                    {
                        SqlCommand command = new SqlCommand(query3, connection);

                        command.Connection.Open();
                        command.ExecuteNonQuery();
                        command.Connection.Close();

                    }


                    //   textBox1.Clear();
                    //     textBox3.Clear();
                    //   comboBox3.ResetText();

                    textBox2.Clear();
                    textBox3.Clear();
                    comboBox3.ResetText();
                    comboBox1.ResetText();
                }

                string connectionString2 = "Data Source=LPMSW09000012JD\\SQLEXPRESS;Initial Catalog=Pharmacies;Integrated Security=True";
                string query2 = "UPDATE Liguanea_Lane2 SET Progress= '1' where code = '" + comboBox2.Text + "'; ";


                using (SqlConnection connection = new SqlConnection(connectionString2))
                {
                    SqlCommand command = new SqlCommand(query2, connection);
                    command.Connection.Open();
                    command.ExecuteNonQuery();
                }
                //this.liguanea_ProgressTableAdapter1.Fill(this.pharmaciesDataSet7.Liguanea_Progress);
                comboBox2.SelectedIndex = comboBox2.SelectedIndex + 1;
                //current = liguaneaLane2BindingSource.Position;
                //this.liguanea_Lane2TableAdapter.Fill(this.pharmaciesDataSet3.Liguanea_Lane2);
                refreshDataGrid2();
                if (dataGridView1.CurrentRow != null)
                {

                    dataGridView1.CurrentCell =
                        dataGridView1
                        .Rows[Math.Min(dataGridView1.CurrentRow.Index + 1, dataGridView1.Rows.Count - 1)]
                        .Cells[dataGridView1.CurrentCell.ColumnIndex];
                    // liguaneaLane2BindingSource.Position = Math.Min(current + 1, liguaneaLane2BindingSource.Count - 1);
                }
            }
        }
    }

Answer 1

您可以使用ComboBox的TextChanged事件查看列表中是否存在輸入文本：

   private void comboBox1_TextChanged(object sender, EventArgs e)
        {
            ComboBox c = ((ComboBox)sender);
            string[] items = c.Items.OfType<string>().ToArray();
            bool matched = items.Any(i => i == c.Text.Trim().ToLower());
        }

您可以以TextChanged事件將為其分配值的形式全局聲明matched布爾值，然后可以在其他方法中使用它，例如：

    void Button_Click(object sender, e EventArgs){
         if(matched)
    {
         //do something
    } else{
        // show an error message
    }

}