C#:无法将“System.Int64"类型的对象转换为“System.Int32"类型

本文介绍了C#:无法将“System.Int64"类型的对象转换为“System.Int32"类型的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我的代码如下:

Dictionary<object, object> dict = ... Color = (int)dict.GetValue("color");

当我将 Color 转换为 int 时，出现以下异常:

When I convert the Color to an int, I get the following exception:

System.InvalidCastException:无法转换类型的对象System.Int64"输入System.Int32".

System.InvalidCastException: Unable to cast object of type 'System.Int64' to type 'System.Int32'.

我不知道为什么我不能从 long 转换为 int.我知道该值小于 0xFFFFFF(24 位)，因为它是一种颜色.

I am not sure why I can't just cast from a long to an int. I know for a fact that the value is less than 0xFFFFFF (24 bits) since it is a color.

我尝试使用 unchecked 但这也无济于事.

I tried using unchecked but that didn't help either.

推荐答案

您必须首先 unbox 值作为字典的值类型是 object.

You must first unbox the value as the dictionary's value type is object.

Dictionary<object, object> dict = ... Color = (int)(long)dict.GetValue("color");