StringBuilder sb = new StringBuilder(256); 长度可以超过256吗

StringBuilder sb = new StringBuilder(256); 的长度可以超过256。在这个例子中，256只是初始容量，而不是限制长度的上限。StringBuilder类会根据需要自动调整其内部缓冲区的大小，以容纳更多的字符。因此，你可以向StringBuilder对象中添加超过256个字符的内容，而不会出现错误或异常。

以下是一个示例，演示了如何向StringBuilder对象中添加超过256个字符的内容：

StringBuilder sb = new StringBuilder(256);
sb.Append("This is a long string that exceeds the initial capacity of 256 characters. ");
sb.Append("It can continue to grow as more characters are added. ");

// 添加超过256个字符的内容
for (int i = 0; i < 200; i++)
{
    sb.Append("a");
}

Console.WriteLine(sb.ToString()); // 输出：This is a long string that exceeds the initial capacity of 256 characters. It can continue to grow as more characters are added. aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa