在CheckBoxList中使用数据源

我在Windows窗体应用程序中使用CheckBoxList，并尝试为其应用数据源。

有一个DataTable，’dt’，列id ， name和ischecked ，我使用这样的代码：

 ((ListBox)MyCheckBoxList).DataSource = dt; ((ListBox)MyCheckBoxList).DisplayMember = "name"; ((ListBox)MyCheckBoxList).ValueMember = "id"; 

如何为MyCheckBoxList中的所有项设置CheckState？

我将此值保存在我的数据表中，并希望将它们与MyCheckBoxList链接。

Answer 1

我分两个步骤决定了我的问题。 首先，我应用了数据源，然后在圆圈中为每个项设置Checked属性，如下面的代码所示：

 ((ListBox)MyCheckBoxList).DataSource = dt; ((ListBox)MyCheckBoxList).DisplayMember = "name"; ... for (int i = 0; i < folloving.Items.Count; i++ ) { DataRowView row = (DataRowView)MyCheckBoxList.Items[i]; bool isChecked = Convert.ToBoolean(row["checked"]); MyCheckBoxList.SetItemChecked(i, isChecked); } 

Answer 2

作为另一种解决方法，我实现了CheckedListBox.Format事件以自动使用数据更新显示的CheckedState; 并实现CheckedListBox.ItemCheck事件以使用CheckedState自动更新数据。

 private DataTable myDataTable = null; private BindingSource myBindingSource = new BindingSource(); // Column Name Constants private const string C_ITEM_INDEX = "Item_Index"; // CheckedListBox Item's Index private const string C_ITEM_TEXT = "Item_Text"; // Item's Text private const string C_ITEM_CHECKED = "Item_Checked"; // Item's Checked State private const string C_DATA_KEY = "Data_Key"; // Arbitrary Key Value for Relating Item to Other Data private void Startup() { // Create DataTable // This DataTable has 4 Columns described by the constants above myDataTable = new DataTable(); myDataTable.Columns.Add(new DataColumn(C_ITEM_INDEX, typeof(Int32))); myDataTable.Columns[C_ITEM_INDEX].DefaultValue = 0; myDataTable.Columns.Add(new DataColumn(C_ITEM_TEXT, typeof(string))); myDataTable.Columns[C_ITEM_TEXT].DefaultValue = ""; // I personally like Integer 1=true, 0=false values. typeof(bool) will also work. myDataTable.Columns.Add(new DataColumn(C_ITEM_CHECKED, typeof(Int32))); myDataTable.Columns[C_ITEM_CHECKED].DefaultValue = 0; // Other columns can be included in the DataTable myDataTable.Columns.Add(new DataColumn(C_DATA_KEY, typeof(Int32))); myDataTable.Columns[C_DATA_KEY].DefaultValue = 0; myDataTable.AcceptChanges(); // Bind the DataTable's DefaultView to the CheckedListBox myBindingSource.DataSource = myDataTable.DefaultView; this.myCheckedListBox.DataSource = myBindingSource; // Set the DisplayMember to the DataColumn you want displayed as the CheckedListBox Items's Text this.myCheckedListBox.DisplayMember = C_ITEM_TEXT; // Set the ValueMember to the Data. Note: The ValueMember is not displayed and is Not the CheckBox value. this.myCheckedListBox.ValueMember = C_DATA_KEY; // Hookup Event Handler for the CheckedListBox.Format Event. /// * The Format event enables us to just in time update the CheckBoxes with the values in the DataTable this.myCheckedListBox.Format += myCheckedListBox_Format; // Hookup Event Handler for the CheckedListBox.ItemCheck Event. /// * The ItemCheck event enables us to just in time update the DataTable with the values from the Item CheckBoxes this.myCheckedListBox.ItemCheck += myCheckedListBox_ItemCheck; } void myCheckedListBox_Format(object sender, ListControlConvertEventArgs e) { /// * The Format event enables us to just in time update the CheckBoxes with the values in the DataTable // Retrieve the Index of the Item in the CheckedListBox by finding the DataRowView in the BindingSource // Note: Use a column with unique values for the BindingSource.Find() function int listindex = myBindingSource.Find(C_ITEM_INDEX, ((DataRowView)e.ListItem)[C_ITEM_INDEX]); // The argument, e.ListItem, is the current DataRowView in the DataTable's DefaultView // Check to see if the checkbox value is different from the data if (((CheckedListBox)sender).GetItemChecked(listindex) != Convert.ToBoolean(((DataRowView)e.ListItem)[C_ITEM_CHECKED])) { // Set the CheckList Item's CheckState to match the data ((CheckedListBox)sender).SetItemChecked(listindex, Convert.ToBoolean(((DataRowView)e.ListItem)[C_ITEM_CHECKED])); } } void myCheckedListBox_ItemCheck(object sender, ItemCheckEventArgs e) { /// * The ItemCheck event enables us to just in time update the DataTable with the values from the Item CheckBoxes // Update the data with the new CheckState value. if (e.NewValue == CheckState.Checked) { myDataTable.DefaultView[e.Index][C_ITEM_CHECKED] = 1; } else { myDataTable.DefaultView[e.Index][C_ITEM_CHECKED] = 0; } // Update other data values too if you need to. } 

Answer 3

我不确定是否有办法通过ValueMember属性设置检查。

你可以试一试：

 foreach (DataRow item in dt.Rows) { MyCheckedListBox.Items.Add(item["Name"].ToString(), Convert.ToBoolean(item["Checked"])); }