当前位置: 首页>>代码示例>>C#>>正文


C# Queryable.Single方法代码示例

本文整理汇总了C#中System.Linq.Queryable.Single方法的典型用法代码示例。如果您正苦于以下问题:C# Queryable.Single方法的具体用法?C# Queryable.Single怎么用?C# Queryable.Single使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。


在下文中一共展示了Queryable.Single方法的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。

示例1:

// Create two arrays.
string[] fruits1 = { "orange" };
string[] fruits2 = { "orange", "apple" };

// Get the only item in the first array.
string fruit1 = fruits1.AsQueryable().Single();

Console.WriteLine("First query: " + fruit1);

try
{
    // Try to get the only item in the second array.
    string fruit2 = fruits2.AsQueryable().Single();
    Console.WriteLine("Second query: " + fruit2);
}
catch (System.InvalidOperationException)
{
    Console.WriteLine(
        "Second query: The collection does not contain exactly one element."
        );
}
开发者ID:.NET开发者,项目名称:System.Linq,代码行数:21,代码来源:Queryable.Single

输出:

First query: orange
    Second query: The collection does not contain exactly one element

示例2:

string[] fruits = { "apple", "banana", "mango", 
                      "orange", "passionfruit", "grape" };

// Get the only string in the array whose length is greater than 10.
string fruit1 = fruits.AsQueryable().Single(fruit => fruit.Length > 10);

Console.WriteLine("First Query: " + fruit1);

try
{
    // Try to get the only string in the array
    // whose length is greater than 15.
    string fruit2 = fruits.AsQueryable().Single(fruit => fruit.Length > 15);
    Console.WriteLine("Second Query: " + fruit2);
}
catch (System.InvalidOperationException)
{
    Console.Write("Second Query: The collection does not contain ");
    Console.WriteLine("exactly one element whose length is greater than 15.");
}
开发者ID:.NET开发者,项目名称:System.Linq,代码行数:20,代码来源:Queryable.Single

输出:

First Query: passionfruit
    Second Query: The collection does not contain exactly one 
    element whose length is greater than 15.

示例3: Main

//引入命名空间
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;

public class MainClass{
   public static void Main(){
            int[] numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9};
            var query = numbers.Single(n => n > 8);
            Console.Write(query);
   }
}
开发者ID:C#程序员,项目名称:System.Linq,代码行数:14,代码来源:Queryable.Single


注:本文中的System.Linq.Queryable.Single方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。