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下面是一段非常简单的C#源码,程序中首先定义单精度浮点数f,并对其进行赋值,运算后取整转换,最后输出计算结果,1.3*100取整后应为130,但程序给出的结果为129。
using System;
namespace testPro
{
class Program
{
static void Main()
{
float f = 1.3F; //step 1
int ret = (int)(f * 100); //step 2
Console.WriteLine(ret);//step 3
//result is 129 !!!!!!!!!!! why??
}
}
}
如果将step 2分解为以下两条语句,则结果为130。
float temp = f * 100;
int ret = (int)temp;
测试环境:
Windows Server 2003
Visual Studio 2005(8.050727)
Microsoft .NET Framework 2.0.50727