Csharp 为什么 C# IndexOf 搜索空字符返回零

下面是我使用的示例代码.净核心6:

using System;

namespace testTerminator
{
    class Program
    {
        static void Main(string[] args)
        {
            // Given an array of bytes:
            byte[] array = {72, 101, 108, 108, 111, 0, 0, 32, 72, 101};
            // Converted to a string:
            string data = System.Text.Encoding.ASCII.GetString(array);
            
            // Why does the following line not return the position
            // of the null characters?
            int terminator = data.IndexOf("\0\0");  // returns 0

            // Output:
            Console.WriteLine("Data is '{0}'", data);
            Console.WriteLine("Found terminator at {0}", terminator);

            // Verify null characters are still in the data string:
            byte[] dataBytes = System.Text.Encoding.ASCII.GetBytes(data);
            for (int i = 0; i<dataBytes.Length; i++){
                Console.Write("{0},", dataBytes[i]);
            }
            Console.WriteLine();
        }
    }
}

这将产生以下输出:

Data is 'Hello He'
Found terminator at 0
72,101,108,108,111,0,0,32,72,101,

当空字符位于位置6时，为什么IndexOf("\0\0")返回零？