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嗨，伙计们说我有一个带有类型字典的对象

我已经制作了一个函数，可以将数据添加到字典并使用反射从字典中获取数据。

我的问题是如何使用反射修改字典中的项目？

代码示例（不使用反射）：

dictionary<string, string> dict = new dictionary<string, string>();
dict.add("key1", "data1");
dict.add("key2", "data2");
console.writeline(dict["key2"]) // <- made using dynamic since it wont store to the objact data (made from relfection)

// code above already accomplished using reflection way
// code below, don't know how to accomplish using reflection way

dict["key2"] = "newdata" // <- how to modify the value of the selected item in object data (made from using reflection)
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2 回答 2

1

您需要找到所需的索引器属性并通过它设置值：

object key = //
object newValue = //
PropertyInfo indexProp = dict.GetType()
    .GetProperties()
    .First(p => p.GetIndexParameters().Length > 0 && p.GetIndexParameters()[0].ParameterType == key.GetType());

indexProp.SetValue(dict, newValue, new object[] { key });

如果您知道您正在处理通用字典，则可以直接获取该属性，即

PropertyInfo indexProp = dict.GetType().GetProperty("Item");
于 2013-05-22T08:15:51.817 回答
0 
        var dictionary = new Dictionary<string, string>
        {
            { "1", "Jonh" },
            { "2", "Mary" },
            { "3", "Peter" },
        };

        Console.WriteLine(dictionary["1"]); // outputs "John"

        // this is the indexer metadata;
        // indexer properties are named with the "Item"
        var prop = dictionary.GetType().GetProperty("Item");

        // the 1st argument - dictionary instance,
        // the second - new value
        // the third - array of indexers with single item, 
        // because Dictionary<TKey, TValue>.Item[TKey] accepts only one parameter
        prop.SetValue(dictionary, "James", new[] { "1" });

        Console.WriteLine(dictionary["1"]); // outputs "James"
于 2013-05-22T08:17:31.390 回答