.NET Framework Class Library  

INameCreationService Interface

Provides a service that can generate unique names for objects.

For a list of all members of this type, see INameCreationService Members.

[Visual Basic]
Public Interface INameCreationService
[C#]
public interface INameCreationService
[C++]
public __gc __interface INameCreationService
[JScript]
public interface INameCreationService

Remarks

A DesignerLoader can implement this service to provide a way for a designer to create new, unique names for objects. If this service is not available, the designer uses a default implementation.

Example

[Visual Basic] 
Imports System
Imports System.ComponentModel.Design
Imports System.ComponentModel.Design.Serialization
Imports System.Globalization

Public Class NameCreationService
    Implements System.ComponentModel.Design.Serialization.INameCreationService

    Public Sub New()
    End Sub

    ' Creates an identifier for a particular data type that does not conflict 
    ' with the identifiers of any components in the specified collection
    Public Function CreateName(ByVal container As System.ComponentModel.IContainer, ByVal dataType As System.Type) As String Implements INameCreationService.CreateName
        ' Create a basic type name string
        Dim baseName As String = dataType.Name
        Dim uniqueID As Integer = 1

        Dim unique As Boolean = False
        ' Continue to increment uniqueID numeral until a unique ID is located.
        While Not unique
            unique = True
            ' Check each component in the container for a matching 
            ' base type name and unique ID.
            Dim i As Integer
            For i = 0 To container.Components.Count - 1
                ' Check component name for match with unique ID string.
                If container.Components(i).Site.Name.StartsWith((baseName + uniqueID.ToString())) Then
                    ' If a match is encountered, set flag to recycle 
                    ' collection, increment ID numeral, and restart.
                    unique = False
                    uniqueID += 1
                    Exit For
                End If
            Next i
        End While

        Return baseName + uniqueID.ToString()
    End Function

    ' Returns whether the specified name contains 
    ' all valid character types.
    Public Function IsValidName(ByVal name As String) As Boolean Implements INameCreationService.IsValidName
        Dim i As Integer
        For i = 0 To name.Length - 1
            Dim ch As Char = name.Chars(i)
            Dim uc As UnicodeCategory = [Char].GetUnicodeCategory(ch)
            Select Case uc
                Case UnicodeCategory.UppercaseLetter, UnicodeCategory.LowercaseLetter, UnicodeCategory.TitlecaseLetter, UnicodeCategory.DecimalDigitNumber
                Case Else
                    Return False
            End Select
        Next i
        Return True
    End Function

    ' Throws an exception if the specified name does not contain 
    ' all valid character types.
    Public Sub ValidateName(ByVal name As String) Implements INameCreationService.ValidateName
        Dim i As Integer
        For i = 0 To name.Length - 1
            Dim ch As Char = name.Chars(i)
            Dim uc As UnicodeCategory = [Char].GetUnicodeCategory(ch)
            Select Case uc
                Case UnicodeCategory.UppercaseLetter, UnicodeCategory.LowercaseLetter, UnicodeCategory.TitlecaseLetter, UnicodeCategory.DecimalDigitNumber
                Case Else
                    Throw New Exception("The name '" + name + "' is not a valid identifier.")
            End Select
        Next i
    End Sub

End Class

[C#] 
using System;
using System.ComponentModel.Design;
using System.ComponentModel.Design.Serialization;
using System.Globalization;

namespace NameCreationServiceExample
{
    public class NameCreationService : System.ComponentModel.Design.Serialization.INameCreationService
    {
        public NameCreationService()
        {
        }

        // Creates an identifier for a particular data type that does not conflict 
        // with the identifiers of any components in the specified collection.
        public string CreateName(System.ComponentModel.IContainer container, System.Type dataType)
        {
            // Create a basic type name string.
            string baseName = dataType.Name;
            int uniqueID = 1;

            bool unique = false;            
            // Continue to increment uniqueID numeral until a 
            // unique ID is located.
            while( !unique )
            {
                unique = true;
                // Check each component in the container for a matching 
                // base type name and unique ID.
                for(int i=0; i<container.Components.Count; i++)
                {
                    // Check component name for match with unique ID string.
                    if( container.Components[i].Site.Name.StartsWith(baseName+uniqueID.ToString()) )
                    {
                        // If a match is encountered, set flag to recycle 
                        // collection, increment ID numeral, and restart.
                        unique = false;
                        uniqueID++;
                        break;
                    }
                }
            }
            
            return baseName+uniqueID.ToString();
        }

        // Returns whether the specified name contains 
        // all valid character types.
        public bool IsValidName(string name)
        {            
            for(int i = 0; i < name.Length; i++)
            {
                char ch = name[i];
                UnicodeCategory uc = Char.GetUnicodeCategory(ch);
                switch (uc) 
                {
                    case UnicodeCategory.UppercaseLetter:       
                    case UnicodeCategory.LowercaseLetter:     
                    case UnicodeCategory.TitlecaseLetter:                                                  
                    case UnicodeCategory.DecimalDigitNumber:                         
                        break;
                    default:
                        return false;                
                }
            }
            return true;        
         }

        // Throws an exception if the specified name does not contain 
        // all valid character types.
        public void ValidateName(string name)
        {
            for(int i = 0; i < name.Length; i++)
            {
                char ch = name[i];
                UnicodeCategory uc = Char.GetUnicodeCategory(ch);
                switch (uc) 
                {
                    case UnicodeCategory.UppercaseLetter:       
                    case UnicodeCategory.LowercaseLetter:     
                    case UnicodeCategory.TitlecaseLetter:                                                  
                    case UnicodeCategory.DecimalDigitNumber:                         
                        break;
                    default:
                        throw new Exception("The name '"+name+"' is not a valid identifier.");                
                }
            }
        }
     }
}

[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Namespace: System.ComponentModel.Design.Serialization

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Assembly: System (in System.dll)

See Also

INameCreationService Members | System.ComponentModel.Design.Serialization Namespace