无法将 Dictionary<string, string> 添加到 List<Dictionary<string, string>>

健身房代码

尝试将 a 添加Dictionary<string,string>List<Dictionary<string,string>>变量时,我遇到了空引用异常我无法找到原因。

public class MyObject
{
    public List<Dictionary<string, string>> ID_Name_List { get; set; }
}

MyObject obj1 = new MyObject();

Dictionary<string, string> ID_Name_Pair = new Dictionary<string, string>();

ID_Name_Pair.Add("1", "Jane");

List<Dictionary<string, string>> ID_Name_List_2 = new List<Dictionary<string, string>>(); //For Testing

ID_Name_List_2.Add(ID_Name_Pair); //SUCCESS

obj1.ID_Name_List.Add(ID_Name_Pair); //ERROR - System.NullReferenceException: 'Object reference not set to an instance of an object.'

我的obj1.ID_Name_List变量具有相同的List<Dictionary<string, string>>类型ID_Name_List_2

为什么我obj1.ID_Name_ListID_Name_List_2成功时遇到错误

任何帮助将不胜感激

用户2250152

你必须初始化ID_Name_List

public class MyObject
{
    public List<Dictionary<string, string>> ID_Name_List { get; set; }

    public MyObject()
    {
        ID_Name_List = new List<Dictionary<string, string>>();
    }
}

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