public class CarSpecs
{
public String CarName { get; set; }
public String CarMaker { get; set; }
public DateTime CreationDate { get; set; }
}
This is a list and I am trying to figure out an efficient way to sort this list List CarList, containing 6(or any integer amount) Cars, by the Car Make Date. I was going to do Bubble sort, but will that work? Any Help?
这是一个列表,我试图找出一种有效的方法来排序这个列表列表CarList,包含6个(或任何整数)汽车,由汽车生产日期。我打算做冒泡排序,但那会有用吗?任何帮助?
Thanks
谢谢
10 个解决方案
#1
83
The List<T>
class makes this trivial for you, since it contains a Sort
method. (It uses the QuickSort algorithm, not Bubble Sort, which is typically better anyway.) Even better, it has an overload that takes a Comparison<T>
argument, which means you can pass a lambda expression and make things very simple indeed.
List
Try this:
尝试这个:
CarList.Sort((x, y) => DateTime.Compare(x.CreationDate, y.CreationDate));
#2
56
You could use LINQ:
您可以使用LINQ:
listOfCars.OrderBy(x => x.CreationDate);
EDIT: With this approach, its easy to add on more sort columns:
编辑:使用这种方法,它很容易添加更多排序列:
listOfCars.OrderBy(x => x.CreationDate).ThenBy(x => x.Make).ThenBy(x => x.Whatever);
#3
16
The best approach is to implement either IComparable
or IComparable<T>
, and then call List<T>.Sort()
. This will do all the hard work of sorting for you.
最好的方法是实现IComparable或IComparable
#4
14
Another option would be to use a custom comparer:
另一种选择是使用自定义比较器:
using System;
using System.Collections.Generic;
using System.Text;
namespace Yournamespace
{
class CarNameComparer : IComparer<Car>
{
#region IComparer<Car> Members
public int Compare(Car car1, Car car2)
{
int returnValue = 1;
if (car1 != null && car2 == null)
{
returnValue = 0;
}
else if (car1 == null && car2 != null)
{
returnValue = 0;
}
else if (car1 != null && car2 != null)
{
if (car1.CreationDate.Equals(car2.CreationDate))
{
returnValue = car1.Name.CompareTo(car2.Name);
}
else
{
returnValue = car2.CreationDate.CompareTo(car1.CreationDate);
}
}
return returnValue;
}
#endregion
}
}
which you call like this:
你这样称呼:
yourCarlist.Sort(new CarNameComparer());
Note: I didn't compile this code so you might have to remove typo's
注意:我没有编译此代码,因此您可能必须删除拼写错误
Edit: modified it so the comparer compares on creationdate as requested in question.
编辑:对其进行修改,以便比较器按照相关要求对创建日期进行比较。
#5
6
I would just use the build in List.Sort method. It uses the QuickSort algorithm which on average runs in O(n log n).
我只想在List.Sort方法中使用build。它使用QuickSort算法,该算法平均以O(n log n)运行。
This code should work for you, I change your properties to auto-properties, and defined a static CompareCarSpecs method that just uses the already existing DateTime.CompareTo method.
此代码应该适合您,我将您的属性更改为自动属性,并定义一个静态CompareCarSpecs方法,该方法只使用现有的DateTime.CompareTo方法。
class Program
{
static void Main(string[] args)
{
List<CarSpecs> cars = new List<CarSpecs>();
cars.Sort(CarSpecs.CompareCarSpecs);
}
}
public class CarSpecs
{
public string CarName { get; set; }
public string CarMaker { get; set; }
public DateTime CreationDate { get; set; }
public static int CompareCarSpecs(CarSpecs x, CarSpecs y)
{
return x.CreationDate.CompareTo(y.CreationDate);
}
}
Hope this helps.
希望这可以帮助。
#6
3
Putting some of the pieces mentioned here together. This compiles and works in C# 4.x and VS2010. I tested with a WinForm
. So add the method to the WinForm
Main()
. You will need the System.Linq
and System.Generic.Collection
s assemblies at least.
将这里提到的一些部分放在一起。这在C#4.x和VS2010中编译和工作。我用WinForm测试过。所以将方法添加到WinForm Main()。您至少需要System.Linq和System.Generic.Collections程序集。
private void SortCars()
{
List<CarSpecs> cars = new List<CarSpecs>();
List<CarSpecs> carsSorted = new List<CarSpecs>();
cars.Add(new CarSpecs
{
CarName = "Y50",
CarMaker = "Ford",
CreationDate = new DateTime(2011, 4, 1),
});
cars.Add(new CarSpecs
{
CarName = "X25",
CarMaker = "Volvo",
CreationDate = new DateTime(2012, 3, 1),
});
cars.Add(new CarSpecs
{
CarName = "Z75",
CarMaker = "Datsun",
CreationDate = new DateTime(2010, 5, 1),
});
//More Comprehensive if needed
//cars.OrderBy(x => x.CreationDate).ThenBy(x => x.CarMaker).ThenBy(x => x.CarName);
carsSorted.AddRange(cars.OrderBy(x => x.CreationDate));
foreach (CarSpecs caritm in carsSorted)
{
MessageBox.Show("Name: " +caritm.CarName
+ "\r\nMaker: " +caritm.CarMaker
+ "\r\nCreationDate: " +caritm.CreationDate);
}
}
}
public class CarSpecs
{
public string CarName { get; set; }
public string CarMaker { get; set; }
public DateTime CreationDate { get; set; }
}
#7
1
If you're after an efficient way of sorting, I'd advise against using bubble sort and go for a quick sort instead. This page provides a rather good explanation of the algorithm:
如果您正在使用有效的排序方法,我建议不要使用冒泡排序,而是快速排序。该页面提供了一个相当好的算法解释:
http://www.devhood.com/Tutorials/tutorial_details.aspx?tutorial_id=574
http://www.devhood.com/Tutorials/tutorial_details.aspx?tutorial_id=574
Best of luck!
祝你好运!
#8
1
I would avoid writing my own sorting algorithm, but if you are going to anyway, have a look at http://www.sorting-algorithms.com/ for some comparrisons of different sorting algorithms...
我会避免编写自己的排序算法,但无论如何,请查看http://www.sorting-algorithms.com/以获取不同排序算法的一些比较...
#9
1
If you are using 2.0, the following discussion may be useful: C# List<> Sort by x then y
如果您使用的是2.0,则以下讨论可能会有用:C#List <>按x然后y排序
#10
0
If you use delegates (also known as anonymous methods), you won't have to implement any IComparer / IComparable interfaces.
如果使用委托(也称为匿名方法),则不必实现任何IComparer / IComparable接口。
public static void Main(string[] args)
{
List<CarSpecs> list = new List<CarSpecs>();
list.Add(new CarSpecs("Focus", "Ford", new DateTime(2010,1, 2));
list.Add(new CarSpecs("Prius", "Toyota", new DateTime(2012,3, 3));
list.Add(new CarSpecs("Ram", "Dodge", new DateTime(2013, 10, 6));
list.Sort(delegate (CarSpecs first, CarSpecs second)
{
int returnValue = 1;
if((first != null & second != null))
{
if (first.CarName.Equals(second.CarName))
{
if (first.CarMaker.Equals(second.CarMaker))
{
returnValue = first.CreationDate.CompareTo(second.CreationDate);
}
else
{
returnValue = first.CarMaker.CompareTo(second.CarMaker);
}
}
else
{
returnValue = first.CarName.CompareTo(second.CarName);
}
}
return returnValue;
});
}
#1
83
The List<T>
class makes this trivial for you, since it contains a Sort
method. (It uses the QuickSort algorithm, not Bubble Sort, which is typically better anyway.) Even better, it has an overload that takes a Comparison<T>
argument, which means you can pass a lambda expression and make things very simple indeed.
List
Try this:
尝试这个:
CarList.Sort((x, y) => DateTime.Compare(x.CreationDate, y.CreationDate));
#2
56
You could use LINQ:
您可以使用LINQ:
listOfCars.OrderBy(x => x.CreationDate);
EDIT: With this approach, its easy to add on more sort columns:
编辑:使用这种方法,它很容易添加更多排序列:
listOfCars.OrderBy(x => x.CreationDate).ThenBy(x => x.Make).ThenBy(x => x.Whatever);
#3
16
The best approach is to implement either IComparable
or IComparable<T>
, and then call List<T>.Sort()
. This will do all the hard work of sorting for you.
最好的方法是实现IComparable或IComparable
#4
14
Another option would be to use a custom comparer:
另一种选择是使用自定义比较器:
using System;
using System.Collections.Generic;
using System.Text;
namespace Yournamespace
{
class CarNameComparer : IComparer<Car>
{
#region IComparer<Car> Members
public int Compare(Car car1, Car car2)
{
int returnValue = 1;
if (car1 != null && car2 == null)
{
returnValue = 0;
}
else if (car1 == null && car2 != null)
{
returnValue = 0;
}
else if (car1 != null && car2 != null)
{
if (car1.CreationDate.Equals(car2.CreationDate))
{
returnValue = car1.Name.CompareTo(car2.Name);
}
else
{
returnValue = car2.CreationDate.CompareTo(car1.CreationDate);
}
}
return returnValue;
}
#endregion
}
}
which you call like this:
你这样称呼:
yourCarlist.Sort(new CarNameComparer());
Note: I didn't compile this code so you might have to remove typo's
注意:我没有编译此代码,因此您可能必须删除拼写错误
Edit: modified it so the comparer compares on creationdate as requested in question.
编辑:对其进行修改,以便比较器按照相关要求对创建日期进行比较。
#5
6
I would just use the build in List.Sort method. It uses the QuickSort algorithm which on average runs in O(n log n).
我只想在List.Sort方法中使用build。它使用QuickSort算法,该算法平均以O(n log n)运行。
This code should work for you, I change your properties to auto-properties, and defined a static CompareCarSpecs method that just uses the already existing DateTime.CompareTo method.
此代码应该适合您,我将您的属性更改为自动属性,并定义一个静态CompareCarSpecs方法,该方法只使用现有的DateTime.CompareTo方法。
class Program
{
static void Main(string[] args)
{
List<CarSpecs> cars = new List<CarSpecs>();
cars.Sort(CarSpecs.CompareCarSpecs);
}
}
public class CarSpecs
{
public string CarName { get; set; }
public string CarMaker { get; set; }
public DateTime CreationDate { get; set; }
public static int CompareCarSpecs(CarSpecs x, CarSpecs y)
{
return x.CreationDate.CompareTo(y.CreationDate);
}
}
Hope this helps.
希望这可以帮助。
#6
3
Putting some of the pieces mentioned here together. This compiles and works in C# 4.x and VS2010. I tested with a WinForm
. So add the method to the WinForm
Main()
. You will need the System.Linq
and System.Generic.Collection
s assemblies at least.
将这里提到的一些部分放在一起。这在C#4.x和VS2010中编译和工作。我用WinForm测试过。所以将方法添加到WinForm Main()。您至少需要System.Linq和System.Generic.Collections程序集。
private void SortCars()
{
List<CarSpecs> cars = new List<CarSpecs>();
List<CarSpecs> carsSorted = new List<CarSpecs>();
cars.Add(new CarSpecs
{
CarName = "Y50",
CarMaker = "Ford",
CreationDate = new DateTime(2011, 4, 1),
});
cars.Add(new CarSpecs
{
CarName = "X25",
CarMaker = "Volvo",
CreationDate = new DateTime(2012, 3, 1),
});
cars.Add(new CarSpecs
{
CarName = "Z75",
CarMaker = "Datsun",
CreationDate = new DateTime(2010, 5, 1),
});
//More Comprehensive if needed
//cars.OrderBy(x => x.CreationDate).ThenBy(x => x.CarMaker).ThenBy(x => x.CarName);
carsSorted.AddRange(cars.OrderBy(x => x.CreationDate));
foreach (CarSpecs caritm in carsSorted)
{
MessageBox.Show("Name: " +caritm.CarName
+ "\r\nMaker: " +caritm.CarMaker
+ "\r\nCreationDate: " +caritm.CreationDate);
}
}
}
public class CarSpecs
{
public string CarName { get; set; }
public string CarMaker { get; set; }
public DateTime CreationDate { get; set; }
}
#7
1
If you're after an efficient way of sorting, I'd advise against using bubble sort and go for a quick sort instead. This page provides a rather good explanation of the algorithm:
如果您正在使用有效的排序方法,我建议不要使用冒泡排序,而是快速排序。该页面提供了一个相当好的算法解释:
http://www.devhood.com/Tutorials/tutorial_details.aspx?tutorial_id=574
http://www.devhood.com/Tutorials/tutorial_details.aspx?tutorial_id=574
Best of luck!
祝你好运!
#8
1
I would avoid writing my own sorting algorithm, but if you are going to anyway, have a look at http://www.sorting-algorithms.com/ for some comparrisons of different sorting algorithms...
我会避免编写自己的排序算法,但无论如何,请查看http://www.sorting-algorithms.com/以获取不同排序算法的一些比较...
#9
1
If you are using 2.0, the following discussion may be useful: C# List<> Sort by x then y
如果您使用的是2.0,则以下讨论可能会有用:C#List <>按x然后y排序
#10
0
If you use delegates (also known as anonymous methods), you won't have to implement any IComparer / IComparable interfaces.
如果使用委托(也称为匿名方法),则不必实现任何IComparer / IComparable接口。
public static void Main(string[] args)
{
List<CarSpecs> list = new List<CarSpecs>();
list.Add(new CarSpecs("Focus", "Ford", new DateTime(2010,1, 2));
list.Add(new CarSpecs("Prius", "Toyota", new DateTime(2012,3, 3));
list.Add(new CarSpecs("Ram", "Dodge", new DateTime(2013, 10, 6));
list.Sort(delegate (CarSpecs first, CarSpecs second)
{
int returnValue = 1;
if((first != null & second != null))
{
if (first.CarName.Equals(second.CarName))
{
if (first.CarMaker.Equals(second.CarMaker))
{
returnValue = first.CreationDate.CompareTo(second.CreationDate);
}
else
{
returnValue = first.CarMaker.CompareTo(second.CarMaker);
}
}
else
{
returnValue = first.CarName.CompareTo(second.CarName);
}
}
return returnValue;
});
}