C#中对象的输出
2013-08-09 17:10 by TangPro, 111 阅读, 0 评论, 收藏, 编辑
假设有个Costmer类如下:
class Costmer { public string Id { get; set; } public string City { get; set; } public string Country { get; set; } public string Region { get; set; } public string Sales { get; set; } public Costmer(string id,string city,string country,string region,string sales)//构造函数 { Id = id; City = city; Country = country; Region = region; Sales = sales; } public override string ToString()//重写ToString()方法,以便于输出 { return "ID:" + Id + " City:" + City + " Country:" + Country + " Region:" + Region + " Sales:" + Sales; } }
创建两个 Costmer 类的实例,然后分别输出:
Costmer c = new Costmer("01", "乐山", "中国", "四川", "999"); Costmer d = new Costmer("02", "成都", "中国", "四川", "123"); Console.WriteLine(c); Console.WriteLine(d);
结果如下:
我们也可以不完全输出类的值,只输出一部分信息,比如我们这里只输出:ID,City,Country的值:
则代码如下:
Costmer c = new Costmer("01", "乐山", "中国", "四川", "999"); Costmer d = new Costmer("02", "成都", "中国", "四川", "123"); Console.WriteLine("ID:{0} City={1} Country={2}",c.Id,c.City,c.Country); Console.WriteLine("ID:{0} City={1} Country={2}", d.Id, d.City, d.Country);
结果:
注意:假若 Costmer 类中没有对 ToString()方法进行重写,则输出结果为:
但是当有多个对象的时候,我们需要将这些对象放在集合中,然后再输出,为此,我们需要创建一个泛型集合
创建一个Costmer类的泛型集合,并向集合中添加 对象
List<Costmer> costmers = new List<Costmer>(); costmers.Add(new Costmer("01","乐山","中国","四川","999")); costmers.Add(new Costmer("02","成都","中国","四川","123")); costmers.Add(new Costmer("03", "重庆", "中国", "重庆", "1234"));
输出对象的值:
for (int i = 0; i < costmers.Count; i++) { Console.WriteLine(costmers[i]); }
结果:
同理也可以只输出对象一部分的值: 在"."后加入对象需要输出的属性值即可
for (int i = 0; i < costmers.Count; i++) { Console.WriteLine(costmers[i].City); }
使用Linq输出对象:
var queryResults = from n in costmers where n.Region == "四川" select n; //注意 是两个=号,这是不是赋值,是判断 foreach (var item in queryResults) { Console.WriteLine(item.ToString()); }
结果:
分类: C#基础