INameCreationService Interface

Definition

Provides a service that can generate unique names for objects.

C#
public interface INameCreationService
Derived

Examples

The following example code provides an example INameCreationService implementation. The service can create a unique name based on a type that does not match any names in the specified container. It can also validate a specified name string.

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.");                
                }
            }
        }
     }
}

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.

Methods

CreateName(IContainer, Type)

Creates a new name that is unique to all components in the specified container.

IsValidName(String)

Gets a value indicating whether the specified name is valid.

ValidateName(String)

Gets a value indicating whether the specified name is valid.

Applies to

Tuote Versiot
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1