我想覆盖C#中的List对象,以便添加一个中值方法,如Sum或Average.我已经发现这个功能：
@H_502_2@public static decimal GetMedian(int[] array)
{
int[] tempArray = array;
int count = tempArray.Length;
Array.Sort(tempArray);
decimal medianValue = 0;
if (count % 2 == 0)
{
// count is even,need to get the middle two elements,add them together,then divide by 2
int middleElement1 = tempArray[(count / 2) - 1];
int middleElement2 = tempArray[(count / 2)];
medianValue = (middleElement1 + middleElement2) / 2;
}
else
{
// count is odd,simply get the middle element.
medianValue = tempArray[(count / 2)];
}
return medianValue;
}
你能告诉我怎么做吗
解决方法
使用扩展方法,并复制输入的数组/列表.
@H_502_2@public static decimal GetMedian(this IEnumerable<int> source)
{
// Create a copy of the input,and sort the copy
int[] temp = source.ToArray();
Array.Sort(temp);
int count = temp.Length;
if (count == 0)
{
throw new InvalidOperationException("Empty collection");
}
else if (count % 2 == 0)
{
// count is even,average two middle elements
int a = temp[count / 2 - 1];
int b = temp[count / 2];
return (a + b) / 2m;
}
else
{
// count is odd,return the middle element
return temp[count / 2];
}
}
