什么是正确的方式来处理表适配器和数据集？

Question

我一直在努力使用表适配器和数据集访问接入数据库的项目。我很接近完成，从Visual Studio运行代码分析，并将其与一些错误想出了约需要实现上，我使用这些方法的特定类的IDisposable。虽然我已经看过关于使用dispose方法或使用使用块的一些不同的事情，但我不确定如何使其工作。创建数据集和表适配器，由全班使用全局变量，许多班级将呼吁其他班也将使用不同的表适配器和数据集。我试图创建一个Dispose方法，但我不知道什么时候调用它，我想知道，如果它被称为在错误的时间将它弄坏我的计划。这里是我需要实现IDisposable类的一个样本：

using System; 
    using System.Collections.Generic; 
    using System.Linq; 
    using System.Text; 

namespace recipeDataBase 
{ 
    class NewRecipe : IDisposable 
    { 
     recipiesNewDataSet recipeDataSet = new recipiesNewDataSet(); 
     recipiesNewDataSetTableAdapters.RecipeTableAdapter recipeTableAdapter = new  recipiesNewDataSetTableAdapters.RecipeTableAdapter(); 
    recipiesNewDataSetTableAdapters.RecipeIngredientTableAdapter recipeIngredientTableAdapter = new recipiesNewDataSetTableAdapters.RecipeIngredientTableAdapter(); 
    recipiesNewDataSetTableAdapters.RatingTableAdapter ratingTableAdapter = new recipiesNewDataSetTableAdapters.RatingTableAdapter(); 
    recipeDataBase.recipiesNewDataSetTableAdapters.IngredientTableAdapter ingredientTableAdapter = new recipiesNewDataSetTableAdapters.IngredientTableAdapter(); 
    private RecipeInfo newRecipe; 
    private RatingNum originalRatingNum; 
    private RatingNum newRating; 
    private RecipeInfo originalRecipe; 
    private string[] ingredients; 

    public NewRecipe(RecipeInfo incommingNewRecipe, RatingNum IncommingNewRating, string[] incommingIngredients) 
    { 
     newRecipe = incommingNewRecipe; 
     newRating = IncommingNewRating; 
     ingredients = incommingIngredients; 
     CreateNewRecipe(); 
     UpdateNewRecipe(); 
    } 
    public void CreateNewRecipe() 
    { 
     originalRatingNum = new RatingNum(); 
     originalRecipe = new RecipeInfo(); 
     originalRatingNum.cookingTime = 0; 
     originalRatingNum.easeOfCooking = 0; 
     originalRatingNum.familyRating = 0; 
     originalRatingNum.healthRating = 0; 
     originalRatingNum.userRating = 0; 

     ratingTableAdapter.Fill(recipeDataSet.Rating); 
     ratingTableAdapter.Insert(originalRatingNum.userRating, originalRatingNum.familyRating, originalRatingNum.healthRating, originalRatingNum.easeOfCooking, originalRatingNum.cookingTime); 
     Query getNewRecipeNumbers = new Query(); 
     int newRatingNumber = getNewRecipeNumbers.newRatingNum(); 



     originalRatingNum.ratingNum = newRatingNumber; 
     newRating.ratingNum = newRatingNumber; 
     newRecipe.ratingNum = newRatingNumber; 
     originalRecipe.recipeName = "newRecipe"; 
     originalRecipe.nationality = "newRecipe"; 
     originalRecipe.recipeEvent = "newRecipe"; 
     originalRecipe.source = "newRecipe"; 
     originalRecipe.type = "newRecipe"; 
     originalRecipe.servings = "0"; 
     originalRecipe.ratingNum = newRatingNumber; 


     recipeTableAdapter.Fill(recipeDataSet.Recipe); 
     recipeTableAdapter.Insert(originalRecipe.recipeName, originalRecipe.nationality, originalRecipe.recipeEvent, originalRecipe.source, originalRecipe.type, originalRecipe.servings, originalRecipe.ratingNum); 
     int newRecipeNum = getNewRecipeNumbers.newRecipeNum(); 
     newRecipe.recipeNum = newRecipeNum; 
     originalRecipe.recipeNum = newRecipeNum; 
     recipeDataSet.AcceptChanges(); 
    } 

    public void UpdateNewRecipe() 
    { 
     UpdateRatingNum updateRatingNum = new UpdateRatingNum(originalRatingNum, newRating); 
     UpdateRecipe updateRecipe = new UpdateRecipe(newRecipe, originalRecipe); 

     UpdateIngredients updateIngredients = new UpdateIngredients(ingredients); 
     UpdateRecipeIngredient updateRecpeIngredients = new UpdateRecipeIngredient(ingredients, newRecipe.recipeNum); 
     recipeDataSet.AcceptChanges(); 

    } 


    public void Dispose() 
    { 
     ratingTableAdapter.Dispose(); 
     recipeTableAdapter.Dispose(); 
     recipeTableAdapter.Dispose(); 
     ingredientTableAdapter.Dispose(); 
     recipeDataSet.Dispose(); 
     throw new NotImplementedException(); 
    } 
} 

}

正如你可以看到我做了实现IDisposable并使用自动生成的方法，把所有的表适配器和在那里要处理的数据集，但我该如何使用它以及在哪里？

感谢您的帮助

克雷格

Answer 1

正如在其他的答案中提到的正确方法使用实现IDisposable是withing using块如下目标：

using (var recipe = new NewRecipe()) 
{ 
    //put your code that uses recipe here 
} 

我想做些什么，虽然指出的是正确的实施的IDisposable模式。请注意，MSDN article for the IDisposable interface上有一个完整的示例。

class Recipe : IDisposable 
{ 
    bool isDisposed = false; 
    TableAdapter myDisposableMember; 

    public void Dispose() 
    { 
     Dispose(true); 
     GC.SupressFinalize(this); 
    } 

    public virtual Dispose(bool isDisposing) 
    { 
     if (!isDisposed) //only clean up once 
     { 
      //clean up unmanaged resource here 
      //in this case we don't have any 

      //clean up managed resources (IE those that implemetn IDisposable only if 
      //Dispose() was called (not the case when invoked during finalisation) 
      if (isDisposing) 
      { 
       if(myDisposableMember == null) 
       { 
        myDisposableMember.Dispose() 
        myDisposablemember = null; 
       } 
      } 

      //mark this instance as cleaned up 
      isDisposed = true; 
     } 
    } 

    //if our class has any unmanaged resources you implement a destructor to guarantee 
    //that they're freed. We don't have any here so we don't implement it. 
    //~Recipe() 
    //{ 
    // Dispose(false); 
    //} 
} 

另请注意，在定稿过程中不要抛出异常（IE：~Recipe()）。因此Dispose(bool)不应该抛出异常。

Answer 2

正常模式：

using (var nr = new NewRecipe()) 
{ 
    ... 
} 

但几个音符在这里：

• 了IDisposable接口上的DataSet和DataAdapter是虚设，跳过它们时不会损失太多。
• 你的类具有资源库和域对象的双重作用。考虑将它分成两类。

Answer 3

正确的使用方法是using。只是不要把它在你的手中 -

using(DataAdapter ratingTableAdapter = new DataAdapter()) 
{ 

} 

ratingTableAdapter将得到处置，一旦代码出来using块。