Visual Studio 2010中,StringBuilder.EnsureCapacity()规则变了吗?2012-03-07 博客园 寒飞雨记得以前的规则是“翻倍补余”。当申请增加容量时,EnsureCapacity()函数不管三七二十一,先将字符串容量加倍,如果加倍后的容量大于申请容量,则加倍后的容量即为新容量;如果加倍后的容量仍小于申请容量,则申请容量为新容量。以前:
StringBuilder buffer = new StringBuilder("Hello Kitty!"); //容量为16
buffer.EnsureCapacity(28); //请求把容量增加到28
Console.WriteLine("Length = {0}", buffer.Length);
Console.WriteLine("Capacity = {0}", buffer.Capacity);
结果为:

现在,现在同样的程序,
StringBuilder buffer = new StringBuilder("Hello Kitty!"); //容量为16
buffer.EnsureCapacity(28); //请求把容量增加到28
Console.WriteLine("Length = {0}", buffer.Length);
Console.WriteLine("Capacity = {0}", buffer.Capacity);
结果为:

申请多少,就是多少。规则发生变化了吗?