C# ComboBox 數據源綁定後數據的添加

   由於ComboBox綁定後,數據動態變化會出現一系列"內存保護"錯誤,無意中發現老外寫的一些東西

即在靜態綁定的情況下,不改變數據源,增加ComboBox的選項,這裏用ComboBox.Items.add是會報錯的.

測試表內容如下:

       表TestTable:      SeqNo    Content 
                                   as1         張三 
                                   as2         李四 
                                   33          as11 
                                   55          as22 
                                    丁          ad33

 

代碼如下:

private void Form1_Load(object sender, EventArgs e) { string conditionStr = "as"; this.comboBox1.TextChanged -= new System.EventHandler(this.comboBox1_TextChanged); string str1 = "SELECT Content,SeqNo From TestTable Where (Content like '" + conditionStr + "%' Or SeqNo like '" + conditionStr + "%') Order by Content"; tempDataTable = GetData(str1); comboBox1.DisplayMember = "Content"; comboBox1.DataSource = tempDataTable; comboBox1.AutoCompleteMode = AutoCompleteMode.SuggestAppend; comboBox1.AutoCompleteSource = AutoCompleteSource.ListItems; this.comboBox1.TextChanged += new System.EventHandler(this.comboBox1_TextChanged); } public static DataTable GetComboBoxedDataTable(DataTable oldDataTable, string valueColumn, string textColumn, string topRowValue, string topRowText) { DataTable newDataTable = new DataTable(); newDataTable.Columns.Add(valueColumn); newDataTable.Columns.Add(textColumn); foreach (DataRow oldDR in oldDataTable.Rows) { DataRow newDR = newDataTable.NewRow(); newDR[0] = oldDR[valueColumn].ToString(); newDR[1] = oldDR[textColumn].ToString(); newDataTable.Rows.InsertAt(newDR, newDataTable.Rows.Count); } // Add your 'Select an item' option at the top DataRow dr = newDataTable.NewRow(); dr[0] = topRowValue; dr[1] = topRowText; newDataTable.Rows.InsertAt(dr, 0); return newDataTable; } private void comboBox1_TextChanged(object sender, EventArgs e) { this.comboBox1.TextChanged -= new System.EventHandler(this.comboBox1_TextChanged); comboBox1.DataSource = GetComboBoxedDataTable(tempDataTable, "Content", "SeqNo", "王五", "as3"); this.comboBox1.TextChanged += new System.EventHandler(this.comboBox1_TextChanged); } private DataTable GetData(string strSQl) { DataTable dtData = new DataTable(); using (SqlConnection thisConnection = new SqlConnection( @"Data Source=(local);Initial Catalog=AVE661;Integrated Security=True")) { using (SqlDataAdapter thisAdapter = new SqlDataAdapter( strSQl, thisConnection)) { thisAdapter.Fill(dtData); } thisConnection.Close(); } return dtData; }