CurrencyManager Class
Definition
Manages a list of Binding objects.
public ref class CurrencyManager : System::Windows::Forms::BindingManagerBase
public class CurrencyManager : System.Windows.Forms.BindingManagerBase
type CurrencyManager = class
inherit BindingManagerBase
Public Class CurrencyManager
Inherits BindingManagerBase
- Inheritance
Examples
The following code example binds a TextBox control to a column in a DataTable, gets the CurrencyManager for the binding, and sets its position.
CurrencyManager^ myCurrencyManager;
void BindControl( DataTable^ myTable )
{
// Bind a TextBox control to a DataTable column in a DataSet.
textBox1->DataBindings->Add( "Text", myTable, "CompanyName" );
// Specify the CurrencyManager for the DataTable.
this->myCurrencyManager = dynamic_cast<CurrencyManager^>(this->BindingContext[ myTable ]);
// Set the initial Position of the control.
this->myCurrencyManager->Position = 0;
}
void MoveNext( CurrencyManager^ myCurrencyManager )
{
if ( myCurrencyManager->Position == myCurrencyManager->Count - 1 )
{
MessageBox::Show( "You're at end of the records" );
}
else
{
myCurrencyManager->Position += 1;
}
}
void MoveFirst( CurrencyManager^ myCurrencyManager )
{
myCurrencyManager->Position = 0;
}
void MovePrevious( CurrencyManager^ myCurrencyManager )
{
if ( myCurrencyManager->Position == 0 )
{
MessageBox::Show( "You're at the beginning of the records." );
}
else
{
myCurrencyManager->Position -= 1;
}
}
void MoveLast( CurrencyManager^ myCurrencyManager )
{
myCurrencyManager->Position = myCurrencyManager->Count - 1;
}
private CurrencyManager myCurrencyManager;
private void BindControl(DataTable myTable){
// Bind a TextBox control to a DataTable column in a DataSet.
textBox1.DataBindings.Add("Text", myTable, "CompanyName");
// Specify the CurrencyManager for the DataTable.
myCurrencyManager = (CurrencyManager)this.BindingContext[myTable];
// Set the initial Position of the control.
myCurrencyManager.Position = 0;
}
private void MoveNext(CurrencyManager myCurrencyManager){
if (myCurrencyManager.Position == myCurrencyManager.Count - 1){
MessageBox.Show("You're at end of the records");
}
else{
myCurrencyManager.Position += 1;
}
}
private void MoveFirst(CurrencyManager myCurrencyManager){
myCurrencyManager.Position = 0;
}
private void MovePrevious(CurrencyManager myCurrencyManager ){
if(myCurrencyManager.Position == 0) {
MessageBox.Show("You're at the beginning of the records.");
}
else{
myCurrencyManager.Position -= 1;
}
}
private void MoveLast(CurrencyManager myCurrencyManager){
myCurrencyManager.Position = myCurrencyManager.Count - 1;
}
' Place the next line into the Declarations section of the form.
Private myCurrencyManager As CurrencyManager
Private Sub BindControl(myTable As DataTable)
' Bind a TextBox control to a DataTable column in a DataSet.
TextBox1.DataBindings.Add("Text", myTable, "CompanyName")
' Specify the CurrencyManager for the DataTable.
myCurrencyManager = CType(me.BindingContext(myTable), CurrencyManager)
' Set the initial Position of the control.
myCurrencyManager.Position = 0
End Sub
Private Sub MoveNext(myCurrencyManager As CurrencyManager)
If myCurrencyManager.Position = myCurrencyManager.Count - 1 Then
MessageBox.Show("You're at end of the records")
Else
myCurrencyManager.Position += 1
End If
End Sub
Private Sub MoveFirst(myCurrencyManager As CurrencyManager)
myCurrencyManager.Position = 0
End Sub
Private Sub MovePrevious(myCurrencyManager As CurrencyManager)
If myCurrencyManager.Position = 0 Then
MessageBox.Show("You're at the beginning of the records.")
Else
myCurrencyManager.Position -= 1
End if
End Sub
Private Sub MoveLast(myCurrencyManager As CurrencyManager)
myCurrencyManager.Position = myCurrencyManager.Count - 1
End Sub
Remarks
The CurrencyManager derives from the BindingManagerBase class. Use the BindingContext to return either a CurrencyManager or a PropertyManager. The actual object returned depends on the data source and data member passed to the Item[Object] property of the BindingContext. If the data source is an object that can return only a single property (instead of a list of objects), the type will be a PropertyManager. For example, if you specify a TextBox as the data source, a PropertyManager will be returned. If, on the other hand, the data source is an object that implements the IList, IListSource, or IBindingList interface, a CurrencyManager will be returned.
The Current property returns the current item in the underlying list. To change the current item, set the Position property to a new value. The value must be greater than 0 and must be less than the value of the Count property.
If the underlying data source implements the IBindingList interface, and the AllowNew property is set to true
, you can use the AddNew method.
Fields
finalType |
Specifies the data type of the list. |
listposition |
Specifies the current position of the CurrencyManager in the list. |
onCurrentChangedHandler |
Specifies the event handler for the CurrentChanged event. (Inherited from BindingManagerBase) |
onPositionChangedHandler |
Specifies the event handler for the PositionChanged event. (Inherited from BindingManagerBase) |
Properties
Bindings |
Gets the collection of bindings being managed. (Inherited from BindingManagerBase) |
Count |
Gets the number of items in the list. |
Current |
Gets the current item in the list. |
IsBindingSuspended |
Gets a value indicating whether binding is suspended. (Inherited from BindingManagerBase) |
List |
Gets the list for this CurrencyManager. |
Position |
Gets or sets the position you are at within the list. |
Methods
AddNew() |
Adds a new item to the underlying list. |
CancelCurrentEdit() |
Cancels the current edit operation. |
CheckEmpty() |
Throws an exception if there is no list, or the list is empty. |
EndCurrentEdit() |
Ends the current edit operation. |
Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
GetItemProperties() |
Gets the property descriptor collection for the underlying list. |
GetItemProperties(ArrayList, ArrayList) |
Gets the collection of property descriptors for the binding using the specified ArrayList. (Inherited from BindingManagerBase) |
GetItemProperties(Type, Int32, ArrayList, ArrayList) |
Gets the list of properties of the items managed by this BindingManagerBase. (Inherited from BindingManagerBase) |
GetListName(ArrayList) |
Gets the name of the list supplying the data for the binding using the specified set of bound properties. |
GetType() |
Gets the Type of the current instance. (Inherited from Object) |
MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
OnBindingComplete(BindingCompleteEventArgs) |
Raises the BindingComplete event. (Inherited from BindingManagerBase) |
OnCurrentChanged(EventArgs) |
Raises the CurrentChanged event. |
OnCurrentItemChanged(EventArgs) |
Raises the CurrentItemChanged event. |
OnDataError(Exception) |
Raises the DataError event. (Inherited from BindingManagerBase) |
OnItemChanged(ItemChangedEventArgs) |
Raises the ItemChanged event. |
OnMetaDataChanged(EventArgs) |
Raises the MetaDataChanged event. |
OnPositionChanged(EventArgs) |
Raises the PositionChanged event. |
PullData() |
Pulls data from the data-bound control into the data source, returning no information. (Inherited from BindingManagerBase) |
PushData() |
Pushes data from the data source into the data-bound control, returning no information. (Inherited from BindingManagerBase) |
Refresh() |
Forces a repopulation of the data-bound list. |
RemoveAt(Int32) |
Removes the item at the specified index. |
ResumeBinding() |
Resumes data binding. |
SuspendBinding() |
Suspends data binding to prevents changes from updating the bound data source. |
ToString() |
Returns a string that represents the current object. (Inherited from Object) |
UpdateIsBinding() |
Updates the status of the binding. |
Events
BindingComplete |
Occurs at the completion of a data-binding operation. (Inherited from BindingManagerBase) |
CurrentChanged |
Occurs when the currently bound item changes. (Inherited from BindingManagerBase) |
CurrentItemChanged |
Occurs when the state of the currently bound item changes. (Inherited from BindingManagerBase) |
DataError |
Occurs when an Exception is silently handled by the BindingManagerBase. (Inherited from BindingManagerBase) |
ItemChanged |
Occurs when the current item has been altered. |
ListChanged |
Occurs when the list changes or an item in the list changes. |
MetaDataChanged |
Occurs when the metadata of the List has changed. |
PositionChanged |
Occurs after the value of the Position property has changed. (Inherited from BindingManagerBase) |