标准的Web用户控件中不能有嵌套元素,您需要开发自定义服务器控件来实现这一点。要允许自定义服务器控件中的嵌套元素,您需要使用 PersistenceMode
属性并将其设置为 InnerProperty
。
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
[PersistenceMode(PersistenceMode.InnerProperty)]
public ItemCollection Items
{
get
{
if (itemCollection == null)
{
if (itemArrayList == null)
{
this.EnsureChildControls();
if (itemArrayList == null)
itemArrayList = new ArrayList();
}
itemCollection = new ItemCollection(itemArrayList);
}
return itemCollection;
}
}
下面是我创建的一个控件的示例:
日程表格控件
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
[PersistenceMode(PersistenceMode.InnerProperty)]
public ScheduleGridColumnCollection Columns
{
get
{
if (scheduleColumnsCollection == null)
{
if (scheduleColumnsArrayList == null)
{
this.EnsureChildControls();
if (scheduleColumnsArrayList == null)
scheduleColumnsArrayList = new ArrayList();
}
scheduleColumnsCollection = new ScheduleGridColumnCollection(scheduleColumnsArrayList);
}
return scheduleColumnsCollection;
}
}
ScheduleGridColumn class
#region schedule column
[PersistChildren(true)]
public sealed class ScheduleGridColumn : DataGridColumn, INamingContainer
{
#region private member variables
private bool editModeEnabled;
private bool aggregateColumn;
private string uniqueName;
private string dataFieldName;
private string aggregateKey;
private string dataFormatString;
private ITemplate editTemplate = null;
#endregion
#region constructor
public ScheduleGridColumn()
{
dataFieldName = String.Empty;
dataFormatString = String.Empty;
uniqueName = String.Empty;
editModeEnabled = false;
}
#endregion
#region properties
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible),
PersistenceMode(PersistenceMode.InnerProperty),
TemplateInstance(TemplateInstance.Single)]
public ITemplate EditTemplate
{
get
{
return editTemplate;
}
set
{
editTemplate = value;
}
}
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public string UniqueName
{
get
{
return uniqueName;
}
set
{
uniqueName = value;
}
}
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public string DataField
{
get
{
return dataFieldName;
}
set
{
dataFieldName = value;
}
}
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public string DataFormatString
{
get
{
return dataFormatString;
}
set
{
dataFormatString = value;
}
}
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public bool EditModeEnabled
{
get
{
return editModeEnabled;
}
set
{
editModeEnabled = value;
}
}
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public bool AggregateColumn
{
get
{
return aggregateColumn;
}
set
{
aggregateColumn = value;
}
}
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
public string AggregateKey
{
get
{
return aggregateKey;
}
set
{
aggregateKey = value;
}
}
#endregion
}
#endregion
ScheduleGridColumnCollection class
#region schedule column collection
[PersistChildren(true)]
public sealed class ScheduleGridColumnCollection : ICollection
{
#region member variables
private ArrayList ItemArray;
private string columnGroupTitle;
#endregion
#region constructors
public ScheduleGridColumnCollection(ArrayList items)
{
ItemArray = items;
}
#endregion
#region methods
public ScheduleGridColumn FindColumnDataField(string dataFieldName)
{
ScheduleGridColumn column = new ScheduleGridColumn();
foreach (ScheduleGridColumn item in ItemArray.Cast<ScheduleGridColumn>())
{
if (item.DataField == dataFieldName)
{
column = item;
break;
}
}
return column;
}
public bool ContainsColumnWithDataField(string dataFieldName)
{
foreach (ScheduleGridColumn item in ItemArray.Cast<ScheduleGridColumn>())
if (item.DataField == dataFieldName)
return true;
return false;
}
public void Add(ScheduleGridColumn item)
{
ItemArray.Add(item);
}
public void AddRange(ScheduleGridColumnCollection itemCollection)
{
foreach (ScheduleGridColumn item in itemCollection)
ItemArray.Add(item);
}
public void Clear()
{
ItemArray.Clear();
}
public IEnumerator GetEnumerator()
{
return ItemArray.GetEnumerator();
}
public void CopyTo(Array array, int index)
{
ItemArray.CopyTo(array, index);
}
#endregion
#region properties
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public ScheduleGridColumn this[int index]
{
get
{
return (ScheduleGridColumn)ItemArray[index];
}
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public ScheduleGridColumn this[string uniqueName]
{
get
{
ScheduleGridColumn dataColumn = null;
foreach (object item in ItemArray)
if (((ScheduleGridColumn)item).UniqueName == uniqueName)
dataColumn = (ScheduleGridColumn)item;
return dataColumn;
}
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public int Count
{
get
{
return ItemArray.Count;
}
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public bool IsReadOnly
{
get
{
return false;
}
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public bool IsSynchronized
{
get
{
return false;
}
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public object SyncRoot
{
get
{
return this;
}
}
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
[Browsable(true)]
public string ColumnGroupTitle
{
get
{
return columnGroupTitle;
}
set
{
columnGroupTitle = value;
}
}
#endregion
}
#endregion
ItemCollection
继承自ICollection
,而集合中的每个元素都继承自DataGridColumn
类。 - James Johnson