在C#中从排序的字典中获取数据时出错

我有一个SortedDictionary< Package,List< string>>.以下是Package类：

using System;

namespace GetPackageInfo
{

public class Package : IComparable, IEquatable<Package> 
{
    public string PackageName;
    public string Version;

    public Package()
    {

    }

    public Package(string packageName)
    {
        this.PackageName = packageName;
    }

    public override int GetHashCode()
    {
        unchecked
        {
            int result = 17;
            result = result * 23 + ((PackageName != null) ? this.PackageName.GetHashCode() : 0);
            result = result * 23 + ((Version != null) ? this.Version.GetHashCode() : 0);
            return result;
        }
    }

    public bool Equals(Package other)
    {
        if (ReferenceEquals(null, other))
        {
            return false;
        }
        if (ReferenceEquals(this, other))
        {
            return true;
        }
        return Equals(this.PackageName, other.PackageName) &&
               Equals(this.Version, other.Version);
    }

    public override bool Equals(object obj)
    {
        Package temp = obj as Package;
        if (temp == null)
            return false;
        return this.Equals(temp);
    }

    public override string ToString()
    {
        return string.Format("PackageName: {0}, Version: {1}", PackageName, Version);
    }

    public int CompareTo(object obj)
    {
        if (obj == null)
            return 1;

        if (obj != null) 
            return (Equals(obj) ? -1 : 1);
        else
            throw new ArgumentException("Object is not a Temperature");
    }

每当我在SortedDictionary上执行Contains或ContainsKey时,即使名称和版本相同,它也不起作用.

if (nugetPackagesInfo.Keys.Any(p => p.Equals(package)))
{
    //List<string> currPackage;
    //nugetPackagesInfo.TryGetValue(package, out currPackage);
    if (!nugetPackagesInfo[package].Contains(packageFile))
    {
        nugetPackagesInfo[package].Add(packageFile);
    }

nuGetPackagesInfo是我的字典对象. Any返回true.但是一旦传递并到达nugetPackagesInfo [package],则它将引发KeyNotFoundException.你能帮我弄清楚吗？我的CompareTo不正确吗？

解决方法:

将CompareTo和GetHashCode更改为这些实现.

public int CompareTo(object obj)
{
    if (obj == null)
        return 1;
    return this.ToString().CompareTo(obj.ToString());
}
public override int GetHashCode()
{
    unchecked
    {
        return ((PackageName != null ? PackageName.GetHashCode() : 0)*397) ^ (Version != null ? Version.GetHashCode() : 0);
    }
}

public override string ToString()
{
    return string.Format("PackageName: {0}, Version: {1}", PackageName??"", Version ?? "");
}

CompareTo-参见documentation.通过使用ToString(),您可以对程序包名称和版本进行比较,而不必自己进行检查.只需确保ToString是正确的即可(我添加了null检查,因此它不会引发Exception).

GetHashCode-不确定从何处获得实现.您需要确保该项目的哈希码始终是唯一的,除非它们确实相等.这是I found on this previous answer on SO的实现,请参见答案中的最后一个编辑.

标签：compareto,sorteddictionary,c
来源： https://codeday.me/bug/20191027/1942807.html