ITaskItem Interface

Definição

Define um item do MSBuild que pode ser consumido e emitido por tarefas.Defines an MSBuild item that can be consumed and emitted by tasks.

public interface class ITaskItem
[System.Runtime.InteropServices.ComVisible(true)]
[System.Runtime.InteropServices.Guid("8661674F-2148-4F71-A92A-49875511C528")]
public interface ITaskItem
type ITaskItem = interface
Public Interface ITaskItem
Derivado
Atributos

Exemplos

O exemplo a seguir mostra o código de uma tarefa que cria um ou mais diretórios.The following example shows the code for a task that creates one or more directories.

using System;
using System.IO;
using System.Security;
using System.Collections;
using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;

namespace Microsoft.Build.Tasks
{
    /*
     * Class: MakeDir
     *
     * An MSBuild task that creates one or more directories.
     *
     */
    public class MakeDir : Task
    {
        // The Required attribute indicates the following to MSBuild:
        //	     - if the parameter is a scalar type, and it is not supplied, fail the build immediately
        //	     - if the parameter is an array type, and it is not supplied, pass in an empty array
        // In this case the parameter is an array type, so if a project fails to pass in a value for the 
            // Directories parameter, the task will get invoked, but this implementation will do nothing,
            // because the array will be empty.
        [Required]
            // Directories to create.
        public ITaskItem[] Directories
        {
            get
            {
                return directories;
            }

            set
            {
                directories = value;
            }
        }

        // The Output attribute indicates to MSBuild that the value of this property can be gathered after the
        // task has returned from Execute(), if the project has an <Output> tag under this task's element for 
        // this property.
        [Output]
        // A project may need the subset of the inputs that were actually created, so make that available here.
        public ITaskItem[] DirectoriesCreated
        {
            get
            {
                return directoriesCreated;
            }
        }

        private ITaskItem[] directories;
        private ITaskItem[] directoriesCreated;

        /// <summary>
        /// Execute is part of the Microsoft.Build.Framework.ITask interface.
        /// When it's called, any input parameters have already been set on the task's properties.
        /// It returns true or false to indicate success or failure.
        /// </summary>
        public override bool Execute()
        {
            ArrayList items = new ArrayList();
            foreach (ITaskItem directory in Directories)
            {
                // ItemSpec holds the filename or path of an Item
                if (directory.ItemSpec.Length > 0)
                {
                    try
                    {
                        // Only log a message if we actually need to create the folder
                        if (!Directory.Exists(directory.ItemSpec))
                        {
                            Log.LogMessage(MessageImportance.Normal, "Creating directory " + directory.ItemSpec);
                            Directory.CreateDirectory(directory.ItemSpec);
                        }

                        // Add to the list of created directories
                        items.Add(directory);
                    }
                    // If a directory fails to get created, log an error, but proceed with the remaining 
                    // directories.
                    catch (Exception ex)
                    {
                        if (ex is IOException
                            || ex is UnauthorizedAccessException
                            || ex is PathTooLongException
                            || ex is DirectoryNotFoundException
                            || ex is SecurityException)
                        {
                            Log.LogError("Error trying to create directory " + directory.ItemSpec + ". " + ex.Message);
                        }
                        else
                        {
                            throw;
                        }
                    }
                }
            }

            // Populate the "DirectoriesCreated" output items.
            directoriesCreated = (ITaskItem[])items.ToArray(typeof(ITaskItem));

            // Log.HasLoggedErrors is true if the task logged any errors -- even if they were logged 
            // from a task's constructor or property setter. As long as this task is written to always log an error
            // when it fails, we can reliably return HasLoggedErrors.
            return !Log.HasLoggedErrors;
        }
    }
}

Comentários

O número de ITaskItem objetos criados durante um Build pode não corresponder exatamente aos itens declarados em um arquivo de projeto pelos seguintes motivos:The number of ITaskItem objects created during a build may not correspond exactly to items declared in a project file for the following reasons:

  • As tarefas às vezes criam itens que não foram declarados no arquivo de projeto.Tasks sometimes create items that were not declared in the project file.

  • Uma coleção de itens pode ser declarada no arquivo de projeto com curingas, o que pode criar muitos itens quando compilado.An item collection can be declared in the project file with wildcards, which could create many items when built.

Propriedades

ItemSpec

Obtém ou define a especificação do item.Gets or sets the item specification.

MetadataCount

Obtém o número de entradas de metadados associadas ao item.Gets the number of metadata entries associated with the item.

MetadataNames

Obtém os nomes das entradas de metadados associadas ao item.Gets the names of the metadata entries associated with the item.

Métodos

CloneCustomMetadata()

Obtém a coleção de metadados personalizados.Gets the collection of custom metadata.

CopyMetadataTo(ITaskItem)

Copia as entradas de metadados personalizadas para outro item.Copies the custom metadata entries to another item.

GetMetadata(String)

Obtém o valor da entrada de metadados especificada.Gets the value of the specified metadata entry.

RemoveMetadata(String)

Remove a entrada de metadados especificada do item.Removes the specified metadata entry from the item.

SetMetadata(String, String)

Adiciona ou altera uma entrada de metadados personalizada ao item.Adds or changes a custom metadata entry to the item.

Aplica-se a