Question

当我尝试将使用方法item.ToDictionary() b的值插入到已经初始化它的Dictionary<string,IList<string>> a时，我收到此错误。

Cannot implicitly conver type System.Collection.Generic.Dictionary<string,List<string>> to System.Collection.Generic.Dictionary<string,IList<string>>

var b = item.ToDictionary();

我使用此函数创建b并尝试插入。

 public class Example {
    private Dictionary<string, IList<string>> a;
    private string c;
    private IList<string> d;

    public Example()
    {
        d = new List<string>();
        a = new Dictionary<string, IList<string>>();
    }
    public void getDictionary()
    {
        var b = c.ToDictionary(e=>c, f=>d.ToList());
        a = b;
    }
}

Answer 1

将b定义为

  var b = c.ToDictionary(e=>c, f=>(IList<string>)d);

Answer 2

问题是d.ToList（）返回List<string>，因此b的类型为Dictionary<string, List<string>>，与Dictionary<string, IList<string>>不同。您可以将其强制转换为IList<string>来解决问题：

public void getDictionary()
{
    var b = c.ToDictionary(e => c, f => (IList<string>) d.ToList());
    a = b;
}

无法隐式转换类型System.Collection.Generic.Dictionary <string，ilist <string>＆gt; to System.Collection.Generic.Dictionary <string，ilist <string>＆gt;

2 个答案: