Class FieldDescriptorCollection

A collection of FieldDescriptor fields with mapping information to columns of the underlying datasource. An instance of this collection is returned by the Fields property of a TableDescriptor.

Inheritance

System.Object

FieldDescriptorCollection

ExpressionFieldDescriptorCollection

UnboundFieldDescriptorCollection

Implements

System.IDisposable

System.Collections.IList

System.Collections.ICollection

System.Collections.IEnumerable

IInsideCollectionEditorProperty

System.ICloneable

System.ComponentModel.ICustomTypeDescriptor

Inherited Members

System.Object.Equals(System.Object, System.Object)

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ReferenceEquals(System.Object, System.Object)

Namespace: Syncfusion.Grouping

Assembly: Syncfusion.Grouping.Base.dll

Syntax

public class FieldDescriptorCollection : IDisposable, IList, ICollection, IEnumerable, IInsideCollectionEditorProperty, ICloneable, ICustomTypeDescriptor

Constructors

FieldDescriptorCollection()

Initializes a new empty collection.

Declaration

public FieldDescriptorCollection()

FieldDescriptorCollection(TableDescriptor)

Initializes a new instance FieldDescriptorCollection collection and attaches it to a TableDescriptor.

Declaration

public FieldDescriptorCollection(TableDescriptor tableDescriptor)

Parameters

Type	Name	Description
TableDescriptor	tableDescriptor	Table Descriptor.

Fields

Empty

A Read-only and empty collection.

Declaration

public static readonly FieldDescriptorCollection Empty

Field Value

Type
FieldDescriptorCollection

Properties

AllowAddRangeChangedWarning

For internal use only. Gets or sets the AllowAddRange property.

Declaration

public static bool AllowAddRangeChangedWarning { get; set; }

Property Value

Type
System.Boolean

Count

Gets the number of elements contained in the collection. The property also ensures that the collection is in sync with the underlying table if changes have been made to the table or the TableDescriptor.

Declaration

public int Count { get; }

Property Value

Type
System.Int32

Remarks

The method calls EnsureInitialized(Boolean).

ExpandProperties

Gets or sets the ExpandProperties.

Declaration

[Obsolete("Replaced with Engine.ShowNestedPropertiesFields")]
public bool ExpandProperties { get; set; }

Property Value

Type
System.Boolean

InsideCollectionEditor

Gets or sets whether the collection is manipulated inside a collection editor.

Declaration

public bool InsideCollectionEditor { get; set; }

Property Value

Type
System.Boolean

IsFixedSize

Returns normally False since this collection has no fixed size. Only when it is Read-only, IsFixedSize returns True.

Declaration

public bool IsFixedSize { get; }

Property Value

Type
System.Boolean

IsModified

Determines if the collection was modified from its default state.

Declaration

public bool IsModified { get; }

Property Value

Type
System.Boolean

IsReadOnly

Determines if the collection is Read-only.

Declaration

public bool IsReadOnly { get; }

Property Value

Type
System.Boolean

IsSynchronized

Gets value for IsSynchronized as false.

Declaration

public bool IsSynchronized { get; }

Property Value

Type
System.Boolean

Item[Int32]

Gets or sets the element at the zero-based index.

Declaration

public FieldDescriptor this[int index] { get; set; }

Parameters

Type	Name	Description
System.Int32	index

Property Value

Type
FieldDescriptor

Item[String]

Gets or sets the element with the specified name.

Declaration

public FieldDescriptor this[string name] { get; set; }

Parameters

Type	Name	Description
System.String	name

Property Value

Type
FieldDescriptor

PopulateForeignKeyFields

Gets or sets the PopulateForeignKeyFields values.

Declaration

[Obsolete("Replaced with Engine.ShowRelationFields")]
public bool PopulateForeignKeyFields { get; set; }

Property Value

Type
System.Boolean

ShouldPopulate

Gets or sets whether collection should check for changes in engine schema or underlying data source schema when EnsureInitialized gets called.

Declaration

public bool ShouldPopulate { get; set; }

Property Value

Type
System.Boolean

Version

The version number of this collection. The version is increased each time the collection or an element within the collection is modified. When getting the version, EnsureInitialized(Boolean) is called to ensure the collection is auto-populated if needed.

Declaration

public int Version { get; set; }

Property Value

Type
System.Int32

Methods

Add(FieldDescriptor)

Adds an object to the end of the collection.

Declaration

public int Add(FieldDescriptor value)

Parameters

Type	Name	Description
FieldDescriptor	value	The element to be added to the end of the collection. The value must not be a NULL reference (Nothing in Visual Basic).

Returns

Type	Description
System.Int32	The zero-based collection index at which the value has been added.

Add(String)

Adds an object to the end of the collection.

Declaration

public int Add(string name)

Parameters

Type	Name	Description
System.String	name	The name of the element to be added to the end of the collection. The value must not be a NULL reference (Nothing in Visual Basic).

Returns

Type	Description
System.Int32	The zero-based collection index at which the value has been added.

AddRange(FieldDescriptor[])

Adds multiple elements at the end of the collection.

Declaration

public void AddRange(FieldDescriptor[] fieldDescriptors)

Parameters

Type	Name	Description
FieldDescriptor[]	fieldDescriptors	The array with elements that should be added to the end of the collection. The array and its elements cannot be NULL references (Nothing in Visual Basic).

CheckType(Object)

Ensure type correctness when a new element is added to the collection.

Declaration

protected virtual void CheckType(object obj)

Parameters

Type	Name	Description
System.Object	obj	The newly added object.

Clear()

Removes all elements from the collection.

Declaration

public void Clear()

Clone()

Creates a copy of the collection and all its elements.

Declaration

public FieldDescriptorCollection Clone()

Returns

Type	Description
FieldDescriptorCollection	A copy of the collection and all its elements.

Contains(FieldDescriptor)

Determines if the element belongs to this collection.

Declaration

public bool Contains(FieldDescriptor value)

Parameters

Type	Name	Description
FieldDescriptor	value	The Object to locate in the collection. The value can be a NULL reference (Nothing in Visual Basic).

Returns

Type	Description
System.Boolean	True if item is found in the collection; otherwise, False.

Remarks

The method ensures that the collection is in sync with the underlying table if changes have been made to the table or the TableDescriptor.

The method calls EnsureInitialized(Boolean).

Contains(String)

Determines if an element with the specified name belongs to this collection.

Declaration

public bool Contains(string name)

Parameters

Type	Name	Description
System.String	name	The name of the element to locate in the collection.

Returns

Type	Description
System.Boolean	True if item is found in the collection; otherwise, False.

CopyTo(FieldDescriptor[], Int32)

Copies the entire collection to a compatible one-dimensional array, starting at the specified index of the target array.

Declaration

public void CopyTo(FieldDescriptor[] array, int index)

Parameters

Type	Name	Description
FieldDescriptor[]	array	The one-dimensional array that is the destination of the elements copied from ArrayList. The array must have zero-based indexing.
System.Int32	index	The zero-based index in array at which copying begins.

CreateCollection(TableDescriptor, FieldDescriptor[])

Called from InternalClone to create a new collection and attach it to the specified table descriptor and insert the specified fields. The fields have already been cloned.

Declaration

protected virtual FieldDescriptorCollection CreateCollection(TableDescriptor td, FieldDescriptor[] fieldDescriptors)

Parameters

Type	Name	Description
TableDescriptor	td	The table descriptor.
FieldDescriptor[]	fieldDescriptors	The cloned field descriptors.

Returns

Type	Description
FieldDescriptorCollection	A new FieldDescriptorCollection.

Dispose()

Disposes the object and collection items.

Declaration

public void Dispose()

EnableOneTimePopulate()

When called the ShouldPopulate property will be set true temporarily until the next EnsureInitialized call and then be reset again to optimize subsequent lookups. The Engine calls this method when schema changes occurred (PropertyChanged was raised).

Declaration

public void EnableOneTimePopulate()

EnsureInitialized(Boolean)

Ensures the collection is initialized and auto-populates the collection on demand.

Declaration

protected virtual void EnsureInitialized(bool populate)

Parameters

Type	Name	Description
System.Boolean	populate	True if collection should auto-populate itself based on properties of the underlying data source.

Equals(Object)

Compares two descriptors.

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
System.Object	obj	Field descriptor to compare.

Returns

Type	Description
System.Boolean	True if the descriptors are equal; False otherwise.

Overrides

System.Object.Equals(System.Object)

GetEnumerator()

Returns an enumerator for the entire collection.

Declaration

public FieldDescriptorCollectionEnumerator GetEnumerator()

Returns

Type	Description
FieldDescriptorCollectionEnumerator	An Enumerator for the entire collection.

Remarks

Enumerators only allow reading the data in the collection. Enumerators cannot be used to modify the underlying collection.

GetHashCode()

Serves as a hash function.

Declaration

public override int GetHashCode()

Returns

Type	Description
System.Int32	Hash code.

Overrides

System.Object.GetHashCode()

IndexOf(FieldDescriptor)

Returns the zero-based index of the occurrence of the element in the collection.

Declaration

public int IndexOf(FieldDescriptor value)

Parameters

Type	Name	Description
FieldDescriptor	value	The element to locate in the collection. The value can be a NULL reference (Nothing in Visual Basic).

Returns

Type	Description
System.Int32	The zero-based index of the occurrence of the element within the entire collection, if found; otherwise, -1.

IndexOf(String)

Searches for the element with the specified name.

Declaration

public int IndexOf(string name)

Parameters

Type	Name	Description
System.String	name	The name of the element to locate in the collection.

Returns

Type	Description
System.Int32	The zero-based index of the occurrence of the element with matching name within the entire collection, if found; otherwise, -1.

InitializeFrom(FieldDescriptorCollection)

Copies settings from another collection and raises Changing and Changed events if differences to the other collection are detected.

Declaration

public void InitializeFrom(FieldDescriptorCollection other)

Parameters

Type	Name	Description
FieldDescriptorCollection	other	The source collection.

Insert(Int32, FieldDescriptor)

Inserts a descriptor element into the collection at the specified index.

Declaration

public void Insert(int index, FieldDescriptor value)

Parameters

Type	Name	Description
System.Int32	index	The zero-based index at which the element should be inserted.
FieldDescriptor	value	The element to insert. The value must not be a NULL reference (Nothing in Visual Basic).

Remarks

The method ensures that the collection is in sync with the underlying table if changes have been made to the table or the TableDescriptor.

IsComplexType(PropertyDescriptor)

Determines if the specified PropertyDescriptor has nested properties.

Declaration

protected virtual bool IsComplexType(PropertyDescriptor pd)

Parameters

Type	Name	Description
System.ComponentModel.PropertyDescriptor	pd	The PropertyDescriptor to be checked.

Returns

Type	Description
System.Boolean	True if nested properties are found; False otherwise.

LoadDefault()

Resets the collection to its default state, auto populates the collection, and marks the collection as modified. Call this method if you want to load the default items for the collection and then modify it (e.g. remove members from the auto-populated list).

Declaration

public void LoadDefault()

Examples

gridGroupingControl1.TableDescriptor.Fields.LoadDefault();
gridGroupingControl1.TableDescriptor.Fields.Remove("MyChildTable.ForeignCategoryID");

Modify()

Marks the collection as modified and avoids auto-population.

Declaration

public void Modify()

OnChanged(ListPropertyChangedEventArgs)

Raises the Changed event.

Declaration

protected virtual void OnChanged(ListPropertyChangedEventArgs e)

Parameters

Type	Name	Description
ListPropertyChangedEventArgs	e	A ListPropertyChangedEventArgs that contains the event data.

OnChanging(ListPropertyChangedEventArgs)

Raises the Changing event.

Declaration

protected virtual void OnChanging(ListPropertyChangedEventArgs e)

Parameters

Type	Name	Description
ListPropertyChangedEventArgs	e	A ListPropertyChangedEventArgs that contains the event data.

Remove(FieldDescriptor)

Removes the specified descriptor element from the collection.

Declaration

public void Remove(FieldDescriptor value)

Parameters

Type	Name	Description
FieldDescriptor	value	The element to remove from the collection. If the value is NULL or the element is not contained in the collection, the method will do nothing.

Remarks

The method ensures that the collection is in sync with the underlying table if changes have been made to the table or the TableDescriptor.

Remove(String)

Removes the specified descriptor element with the specified name from the collection.

Declaration

public void Remove(string name)

Parameters

Type	Name	Description
System.String	name	The name of the element to remove from the collection. If no element with that name is found in the collection, the method will do nothing.

Remarks

The method ensures that the collection is in sync with the underlying table if changes have been made to the table or the TableDescriptor.

RemoveAt(Int32)

Removes the element at the specified index of the collection.

Declaration

public void RemoveAt(int index)

Parameters

Type	Name	Description
System.Int32	index	The zero-based index of the element to remove.

Reset()

Resets the collection to its default state. If the collection is bound to a TableDescriptor, the collection will auto populate itself the next time an item inside the collection is accessed.

Declaration

public void Reset()

ShowAddRangeChangedWarning(String)

Internal only. ShowADdRangeChangedWarning display and warning message when the add range changed.

Declaration

public static void ShowAddRangeChangedWarning(string colName)

Parameters

Type	Name	Description
System.String	colName	The column name.

SuggestName(FieldDescriptor)

Called to get a new default name when a new field descriptor is created (e.g. when pressing "Add" in a collection editor).

Declaration

protected virtual void SuggestName(FieldDescriptor value)

Parameters

Type	Name	Description
FieldDescriptor	value	The field descriptor to be named.

ToString()

Returns string representation of this object.

Declaration

public override string ToString()

Returns

Type	Description
System.String	A System.String that represents the current System.Object.

Overrides

System.Object.ToString()

Events

Changed

Occurs after a property in a nested element or the collection is changed.

Declaration

public event ListPropertyChangedEventHandler Changed

Event Type

Type
ListPropertyChangedEventHandler

Changing

Occurs before a property in a nested element or the collection is changed.

Declaration

public event ListPropertyChangedEventHandler Changing

Event Type

Type
ListPropertyChangedEventHandler

Explicit Interface Implementations

IInsideCollectionEditorProperty.InitializeFrom(Object)

Initialize the Field descriptor from the given object.

Declaration

void IInsideCollectionEditorProperty.InitializeFrom(object other)

Parameters

Type	Name	Description
System.Object	other

ICollection.CopyTo(Array, Int32)

Copies the elements of the System.Collections.ICollection to an System.Array,starting at a particular System.Array index.

Declaration

void ICollection.CopyTo(Array array, int index)

Parameters

Type	Name	Description
System.Array	array	The one-dimensional System.Array that is the destination of the elements copied from System.Collections.ICollection. The System.Array must have zero-based indexing.
System.Int32	index	The zero-based index in array at which copying begins.

ICollection.SyncRoot

Gets an object that can be used to synchronize access to the System.Collections.ICollection.

Declaration

object ICollection.SyncRoot { get; }

Returns

Type
System.Object

IEnumerable.GetEnumerator()

Returns an enumerator that iterates through a collection.

Declaration

IEnumerator IEnumerable.GetEnumerator()

Returns

Type	Description
System.Collections.IEnumerator	Returns an enumerator that iterates through a collection.

IList.Add(Object)

Adds an item to the System.Collections.IList.

Declaration

int IList.Add(object value)

Parameters

Type	Name	Description
System.Object	value	The object to add to the System.Collections.IList.

Returns

Type	Description
System.Int32	The position into which the new element was inserted, or -1 to indicate that the item was not inserted into the collection,

IList.Contains(Object)

Determines whether the System.Collections.IList contains a specific value.

Declaration

bool IList.Contains(object value)

Parameters

Type	Name	Description
System.Object	value	The object to locate in the System.Collections.IList.

Returns

Type	Description
System.Boolean	true if the System.Object is found in the System.Collections.IList; otherwise, false.

IList.get_Item(Int32)

Declaration

object IList.get_Item(int index)

Parameters

Type	Name	Description
System.Int32	index

Returns

Type
System.Object

IList.IndexOf(Object)

Determines the index of a specific item in the System.Collections.IList.

Declaration

int IList.IndexOf(object value)

Parameters

Type	Name	Description
System.Object	value	he object to locate in the System.Collections.IList.

Returns

Type	Description
System.Int32	The index of value if found in the list; otherwise, -1.

IList.Insert(Int32, Object)

Inserts an item to the System.Collections.IList at the specified index.

Declaration

void IList.Insert(int index, object value)

Parameters

Type	Name	Description
System.Int32	index	The zero-based index at which value should be inserted.
System.Object	value	The object to insert into the System.Collections.IList.

IList.Item[Int32]

Gets or sets the element at the specified index.

Declaration

object IList.this[] { get; set; }

Parameters

Type	Name	Description
System.Int32	index	The zero-based index of the element to get or set.

Returns

Type	Description
System.Object	The element at the specified index.

IList.Remove(Object)

Removes the first occurrence of a specific object from the System.Collections.IList.

Declaration

void IList.Remove(object value)

Parameters

Type	Name	Description
System.Object	value	The object to remove from the System.Collections.IList.

IList.set_Item(Int32, Object)

Declaration

void IList.set_Item(int index, object value)

Parameters

Type	Name	Description
System.Int32	index
System.Object	value

ICloneable.Clone()

Crates the copy of the collection and its elements.

Declaration

object ICloneable.Clone()

Returns

Type	Description
System.Object	A new object that is a copy of this instance.

Implements

System.IDisposable

System.Collections.IList

System.Collections.ICollection

System.Collections.IEnumerable

IInsideCollectionEditorProperty

System.ICloneable

System.ComponentModel.ICustomTypeDescriptor