可以說我有一個數組說明代碼:使用FirstorDefault()
Product[] myProducts = new Product[]
{
new Product { ID = 1, name = "Ketchup1", category = "Sauces", price = 200.00m },
new Product { ID = 2, name = "Ketchup2", category = "Sauces", price = 200.00m },
new Product { ID = 3, name = "Ketchup3", category = "Sauces", price = 200.00m }
};
一些項目然後可以說,我嘗試使用這種方法
public Product GetProductById(int id)
{
var product = products.FirstOrDefault((p) => p.Id == id);
if (product == null)
{
throw new HttpResponseException(HttpStatusCode.NotFound);
}
return product;
}
我必須找回從陣列中檢索項閱讀它做什麼,但我沒有得到這裏發生了什麼:
FirstorDefault(p => p.Id == id);
參見:http://msdn.microsoft.com/en-us/library/vstudio/bb311046.aspx – 2013-04-08 07:41:37
它創建一個臨時變量類型的產品,然後比較其'Id'屬性與給定值 – Sandy 2013-04-08 07:41:41
這是一個lambda表達式,[檢查它](http://msdn.microsoft.com/en-gb/library/bb397687.aspx) – fbstj 2013-04-08 07:41:48