如何重构这个方法来降低它的认知复杂度

问题描述

我需要帮助，我正在尝试重构此方法以降低其认知复杂性 sonarqube 显示此问题

private void PopulateBook(Book b)
{
    if (b.page.num001 == null) b.page.num001 = string.Empty;
    if (b.page.num002 == null) b.page.num002 = string.Empty;
    if (b.page.num003 == null) b.page.num003 = string.Empty;
    if (b.page.num004 == null) b.page.num004 = string.Empty;
    if (b.page.num005 == null) b.page.num005 = string.Empty;
    if (b.page.num006 == null) b.page.num006 = string.Empty;
    if (b.page.num007 == null) b.page.num007 = string.Empty;
    if (b.page.num008 == null) b.page.num008 = string.Empty;
    if (b.page.num009 == null) b.page.num009 = string.Empty;
    if (b.page.num010 == null) b.page.num010 = string.Empty;
    if (b.page.num011 == null) b.page.num011 = string.Empty;
    if (b.page.num012 == null) b.page.num012 = string.Empty;
    if (b.page.num013 == null) b.page.num013 = string.Empty;
    if (b.page.num014 == null) b.page.num014 = string.Empty;
    if (b.page.num015 == null) b.page.num015 = string.Empty;
    if (b.page.num016 == null) b.page.num016 = string.Empty;
    if (b.page.num017 == null) b.page.num017 = string.Empty;
    if (b.page.num018 == null) b.page.num018 = string.Empty;
    if (b.page.num019 == null) b.page.num019 = string.Empty;
    if (b.page.num020 == null) b.page.num020 = string.Empty;
}

解决方法

您可以重新设计 Page 类。

我不知道 num001 等是什么，指的是页面上的数字。是词索引吗？ 字符数，具体字符？ 或者完全是别的什么？

但不管它是什么：

public class Page {

   public List<Num> numList

   public Page()
   {
      NumList = InitializeNumList();
   }

   private List<Num> InitializeNumList()
   {
      NumList = new List<Num>{};
      for(int i = 0; i < 20; i++)
      {
          NumList.add(new Num(i))
      }
   }

} 

public class Num
{
   public int Id {get;set;};
   public string SomeString {get;set;}

   public Num(int id)
   {
       Id = id;
       SomeString = "";
   }
}

,

如果您想减少代码行数并假设您的“页面”是一个仅具有这些属性的类 - 那么您可以使用某种反射来使用循环设置属性。

  private static void PopulateBook(Book b)
        {
            var page = b.page;
            PropertyInfo[] properties = typeof(page).GetProperties();
            foreach(var prop in properties)
            {
                if(prop.GetValue(page) == null)
                prop.SetValue(page,String.Empty);
            }
        }