Java getBytes UTF-8编码(Java getBytes UTF-8 encoding)

 您提供的代码中存在一些误解： 
 
byte[] bytearray = new byte[size];
foreach (byte bit in bytearray) 
{
     bit = 0;
}
 
 您似乎认为您正在初始化数组bytearray每个字节为零。 相反，您只需将循环变量bit （不幸命名）设置为零size 。 实际上这个代码甚至不会编译，因为你不能分配给foreach迭代变量。 
 
 此外，您首先不需要初始化：字节数组元素自动初始化为0。 
 
string tobewritten = string.Empty;
foreach (byte bit in bytearray) 
{
     tobewritten += bit.ToString();
}
 
 您希望将数组中每个字节的字符串表示形式组合到要写入的字符串变量中。 由于字符串是不可变的，因此为每个必须进行垃圾收集的元素创建一个新字符串以及为bit创建的字符串，这相对较贵，尤其是当您创建其中一个Stringbuilder - 请改用Stringbuilder 。 
 
 最后，根本不需要所有这些 - 似乎你只想在文本文件中写一堆“0”字符 - 如果你不担心创建一个大的零字符串（它取决于值的size是否有意义）您可以直接创建字符串来执行此操作 - 或者将一个较小的字符串直接写入流中。 
 
using (var file = File.CreateText(newpath))
{
    file.WriteLine(new string('0', size));
}

There are several misunderstandings in the code you provided:
 
byte[] bytearray = new byte[size];
foreach (byte bit in bytearray) 
{
     bit = 0;
}
 
You seem to think that your are initializing each byte in your array bytearray with zero. Instead you just set the loop variable bit (unfortunate naming) to zero size times. Actually this code wouldn't even compile since you cannot assign to the foreach iteration variable.
 
Also you didn't need initialization here in the first place: byte array elements are automatically initialized to 0.
 
string tobewritten = string.Empty;
foreach (byte bit in bytearray) 
{
     tobewritten += bit.ToString();
}
 
You want to combine the string representation of each byte in your array to the string variable tobewritten. Since strings are immutable you create a new string for each element that has to be garbage collected along with the string you created for bit, this is relatively expensive, especially when you create 2048000 one of them - use a Stringbuilder instead.
 
Lastly all of that is not needed at all anyway - it seems you just want to write a bunch of "0" characters to a text file - if you are not worried about creating a single large string of zeros (it depends on the value of size whether this makes sense) you can just create the string directly to do this one go - or alternatively write a smaller string directly to the stream a bunch of times.
 
using (var file = File.CreateText(newpath))
{
    file.WriteLine(new string('0', size));
}