C# 使用不可变集合或减少字段“CreateContactMapping”的可访问性

Question

我在旧项目中的类遇到问题，我不知道如何重构这部分，我从sonarcube收到以下错误消息：

Use an immutable collection or reduce the accessibility of the field(s) 'CreateContactMapping'.Why is this an issue?

这是一段代码

public static readonly Dictionary<string, Func<UpdateContactServiceRequest, object>> UpdateContactMapping =
    new Dictionary<string, Func<UpdateContactServiceRequest, object>>
    {
        { "firstname", req => req.FirstName },
        { "lastname", req => req.LastName },
        { "full_name", req => req.FullName },
        { "email", req => req.Email },
        { "phone", req => req.Phone },
        { "date_of_birth", req => req.BirthDate },
        { "job_title", req => req.JobTitle },
        { "occupation", req => req.Occupation },
        { "renda", req => req.MonthlyIncome },
        { "lifecyclestage", req => req.LifeCycleStage },
        { "hs_lead_status", req => req.LeadStatus },
        { "ali_email_validated", req => req.EmailValidated },
        { "ali_sms_token_validated", req => req.CellphoneValidated },
        { "id_da_proposta_atual", req => req.CurrentProposalId },
        { "contact_type", req => req.ContactType }
    };

如何最好地解决这个问题？

Answer 1

一种解决方案是将

Dictionary

更改为

ImmutableDictionary

，然后在初始化字典后运行

.ToImmutableDictionary()

。

public static readonly ImmutableDictionary<string, Func<UpdateContactServiceRequest, object>> UpdateContactMapping = new Dictionary<string, Func<UpdateContactServiceRequest, object>>
        {
            { "firstname", req => req.FirstName },
            { "lastname", req => req.LastName },
            { "full_name", req => req.FullName },
            { "email", req => req.Email },
            { "phone", req => req.Phone },
            { "date_of_birth", req => req.BirthDate },
            { "job_title", req => req.JobTitle },
            { "occupation", req => req.Occupation },
            { "renda", req => req.MonthlyIncome },
            { "lifecyclestage", req => req.LifeCycleStage },
            { "hs_lead_status", req => req.LeadStatus },
            { "ali_email_validated", req => req.EmailValidated },
            { "ali_sms_token_validated", req => req.CellphoneValidated },
            { "id_da_proposta_atual", req => req.CurrentProposalId },
            { "contact_type", req => req.ContactType }
        }.ToImmutableDictionary();

Answer 2

使用不可变集合：您可以使用不可变集合（例如 ImmutableDictionary>）来代替 Dictionary>。这确保了集合的内容在初始化后不能被修改。这是一个例子：

public static readonly ImmutableDictionary<string, Func<UpdateContactServiceRequest, object>> UpdateContactMapping = ImmutableDictionary<string, Func<UpdateContactServiceRequest, object>>.Empty
    .Add("firstname", req => req.FirstName)
    .Add("lastname", req => req.LastName)
    .Add("full_name", req => req.FullName)
    // Add the rest of the key-value pairs
    ;

减少可访问性：如果您想继续使用Dictionary>，可以减少字段的可访问性，以限制外部代码的直接修改。例如，您可以根据您的要求将可访问性更改为私有或内部。然后，您可以提供公共方法或属性来以受控方式访问字典的内容。

private static readonly Dictionary<string, Func<UpdateContactServiceRequest, object>> UpdateContactMapping = new Dictionary<string, Func<UpdateContactServiceRequest, object>>
{
    { "firstname", req => req.FirstName },
    { "lastname", req => req.LastName },
    // Add the rest of the key-value pairs
};

public static IReadOnlyDictionary<string, Func<UpdateContactServiceRequest, object>> GetUpdateContactMapping()
{
    return UpdateContactMapping;
}