更有效的方法是先将字符串连接起来,然后像这样将其转换为字节数组:
List<string> input = new List<string> { "first", "second" };
string fullString = String.Join(String.Empty, list.ToArray());
byte[] byteArray = Encoding.UTF8.GetBytes(fullString);
如果性能很重要,而且列表中有很多字符串,您可以采用以下方法:
编辑:经过基准测试,此方法确实比上述方法慢。
List<string> input = new List<string> { "first", "second" };
StringBuilder sb = new StringBuilder();
foreach (string s in input )
sb.Append(s);
byte[] byteArray = Encoding.UTF8.GetBytes(sb.ToString());
编辑:
我对本帖中提到的一些方法进行了基准测试。以下是发布版本的输出结果:
ConvertWithString 896ms
ConvertWithStringBuilder 858ms
ConvertWithConcat 1529ms
ConvertWithSelectMany 2234ms
ConvertWithBuffer 904ms
ConvertWithString 501ms
ConvertWithStringBuilder 919ms
ConvertWithConcat 1435ms
ConvertWithSelectMany 2044ms
ConvertWithBuffer 636ms
如果你没有很多字符串,性能似乎并不重要。
以下是代码:
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
namespace ConsoleApplication2
{
internal class Program
{
static byte[] ConvertWithBuffer(List<string> list)
{
int totalSize = list.Sum(x => Encoding.UTF8.GetByteCount(x));
byte[] buffer = new byte[totalSize];
int ix = 0;
foreach (string str in list)
ix += Encoding.UTF8.GetBytes(str, 0, str.Length, buffer, ix);
return buffer;
}
static byte[] ConvertWithConcat(List<string> list) { return Encoding.UTF8.GetBytes(String.Concat(list)); }
static byte[] ConvertWithSelectMany(List<string> list)
{
return list
.SelectMany(line => Encoding.UTF8.GetBytes(line))
.ToArray();
}
static byte[] ConvertWithString(List<string> input)
{
string fullString = String.Join(String.Empty, input.ToArray());
return Encoding.UTF8.GetBytes(fullString);
}
static byte[] ConvertWithStringBuilder(List<string> input)
{
StringBuilder sb = new StringBuilder();
foreach (string s in input)
sb.Append(s);
return Encoding.UTF8.GetBytes(sb.ToString());
}
static IEnumerable<string> CreateList()
{
for (int i = 0; i < 10000000; i++)
yield return i.ToString();
}
static void Main(string[] args)
{
List<string> strings = CreateList().ToList();
Stopwatch stopWatch = Stopwatch.StartNew();
ConvertWithString(strings);
ConvertWithStringBuilder(strings);
ConvertWithConcat(strings);
ConvertWithSelectMany(strings);
ConvertWithBuffer(strings);
stopWatch.Restart();
ConvertWithString(strings);
Console.WriteLine("ConvertWithString {0}ms", stopWatch.ElapsedMilliseconds);
stopWatch.Restart();
ConvertWithStringBuilder(strings);
Console.WriteLine("ConvertWithStringBuilder {0}ms", stopWatch.ElapsedMilliseconds);
stopWatch.Restart();
ConvertWithConcat(strings);
Console.WriteLine("ConvertWithConcat {0}ms", stopWatch.ElapsedMilliseconds);
stopWatch.Restart();
ConvertWithSelectMany(strings);
Console.WriteLine("ConvertWithSelectMany {0}ms", stopWatch.ElapsedMilliseconds);
stopWatch.Restart();
ConvertWithBuffer(strings);
Console.WriteLine("ConvertWithBuffer {0}ms", stopWatch.ElapsedMilliseconds);
Console.WriteLine("press any key...");
Console.ReadKey();
}
}
}
AddRange()
,而不是Add
。 - Disappointed