C#中Dynamic和Dictionary性能比较

开发中需要传递变参，考虑使用 dynamic 还是 dictionary（准确地说是dictionary<string,object>）。

dynamic 的编码体验显著优于 dictionary，如果性能差距不大的话，我会选择使用dynamic。

搜索后没有找到类似对比数据，决定自行实验。

首先使用以下测试代码：

				?

									public void testdynamic()

									{

									var e = calldynamic(new { value = 0 });

									int v = e.value;

									}

									public void testdictionary() 

									{

									var dict = new dictionary<string, object>();

									dict["value"] = 0;

									dict = calldictionary(dict);

									int v = (int)dict["value"];

									}

									private dynamic calldynamic(dynamic test)

									{

									int v = test.value;

									v++;

									return new { value = v };

									}

									private dictionary<string, object> calldictionary(

									dictionary<string, object> test)

									{

									int v = (int)test["value"];

									v++;

									var dict = new dictionary<string, object>();

									dict["value"] = v;

									return dict;

									}

分别比较运行 1次、10次、100次、1000次、1e4次、1e5次、1e6次时间

结果：

C#中Dynamic和Dictionary性能比较

其中dynamic列和dynamic2列的数据分别是：

在一次运行中执行一步测试和在一次运行中连续执行所有测试

分析测试过程和数据，得到以下结论：

1.dynamic首次使用会产生一定的性能损耗

2.无论是否首次使用，使用次数达到一定量级，dynamic性能一定优于dictionary

3.一次运行中连续使用dynamic会显著拉低平均性能损耗

考虑到传递变参可能出现多个参数，以上测试不完全。

使用以下代码进行第二阶段实验：

				?

									public void invokedynamic()

									{

									var e = calldynamic2(

									new { value1 = 0, value2 = 0l, value3 = 0f, value4 = 0.0, value5 = "test" });

									int v1 = e.value1;

									long v2 = e.value2;

									float v3 = e.value3;

									double v4 = e.value4;

									string v5 = e.value5;

									}

									public void invokedictionary()

									{

									var dict = new dictionary<string, object>();

									dict["value1"] = 0;

									dict["value2"] = 0l;

									dict["value3"] = 0f;

									dict["value4"] = 0.0;

									dict["value5"] = "test";

									dict = calldictionary2(dict);

									int v1 = (int)dict["value1"];

									long v2 = (long)dict["value2"];

									float v3 = (float)dict["value3"];

									double v4 = (double)dict["value4"];

									string v5 = (string)dict["value5"];

									}

									private dynamic calldynamic2(dynamic test)

									{

									int v1 = test.value1;

									long v2 = test.value2;

									float v3 = test.value3;

									double v4 = test.value4;

									string v5 = test.value5;

									v1++;

									v2++;

									v3++;

									v4++;

									v5 += "test";

									return new { value1 = v1, value2 = v2, value3 = v3, value4 = v4, value5 = v5 };

									}

									private dictionary<string, object> calldictionary2(

									dictionary<string, object> test)

									{

									int v1 = (int)test["value1"];

									long v2 = (long)test["value2"];

									float v3 = (float)test["value3"];

									double v4 = (double)test["value4"];

									string v5 = (string)test["value5"];

									v1++;

									v2++;

									v3++;

									v4++;

									v5 += "test";

									var dict = new dictionary<string, object>();

									dict["value1"] = v1;

									dict["value2"] = v2;

									dict["value3"] = v3;

									dict["value4"] = v4;

									dict["value5"] = v5;

									return dict;

									}