c# – 用于访问静态数据的设计模式

[AttributeUsage(AttributeTargets.Assembly,AllowMultiple = false)]
public sealed class AssemblyChannelAttribute : Attribute
{
    public ChannelType Type { get; private set; }

    public AssemblyChannelAttribute(ChannelType type)
    {
        this.Type = type;
    }
}

public enum ChannelType
{
    Dev,Beta,PreProd,Prod
}

此属性在程序集上设置：

#if DEBUG
// In release mode,this attribute is set by the MSBuild script
[assembly: AssemblyChannel(ChannelType.Dev)]
#else

正如评论所说,属性的值是在我的MSBuild脚本的编译时设置的(与我的项目过于关联以向您显示此部分).

设置完所有这些后,您可以创建一个简单的单例,如下所示：

public class Credentials
{
    private static readonly Lazy<Credentials> instanceHolder =
        new Lazy<Credentials>(() => new Credentials());

    public IReadOnlyDictionary<string,string> Passwords { get; private set; }

    public Credentials Instance { get { return instanceHolder.Value; } }

    private Credentials()
    {
        var channel = typeof(Credentials).Assembly
            .GetCustomAttributes<AssemblyChannelAttribute>()
            .ElementAt(0)
            .Type;

        switch (channel)
        {
            case ChannelType.Dev:
                this.Passwords = new ReadOnlyDictionary<string,string>(new Dictionary<string,string>
                {
                    ["User1"] = "Pwd1",["User2"] = "Pwd2",// etc
                });
                break;
            case ChannelType.Beta:
                // etc
                break;
            case ChannelType.PreProd:
                // etc
                break;
            case ChannelType.Prod:
                // etc
                break;
        }
    }
}

然后您可以像这样访问您的凭据：

var password = Credentials.Instance.Passwords["User1"];