找到一篇国外的代码，专门来测试这个，
String+
String.Concat
String.Format
StringBuilder
前三个在100个左右字符串差不多，
String.Concat会获得稍微好一点点的性能提高，
String.Format会让你使用起来更方便，
StringBuilder更适合更多更长的字符串拼接，
如果有其它见解，还请指导。
using System;
using System.Diagnostics;
using System.Text;
namespace CompareInstructionExecutionSpeed
{
public delegate void CompareExcecutionSpeed(int loop);
class Program
{
public static string ResultConcatenation = string.Empty;
public static readonly StringBuilder Sb = new StringBuilder();
public static readonly Stopwatch Stopwatch = new Stopwatch(); public static void Main()
{
CompareExcecutionSpeed methods = StringBuilderExecutionSpeed;
methods += StringConcatExecutionSpeed;
methods += ManualConcatenationExecutionSpeed;
methods += StringFormatExecutionSpeed;
//methods+=Some Method -- you can add your method to calculate speed. methods.Invoke();//count Console.ReadKey();
} //Elapsing StringBuilder -------------------------------------------
public static void StringBuilderExecutionSpeed(int loop)
{
Stopwatch.Restart();
for (int i = ; i < loop; i++)
{
ShowPercentProgress(i, loop);
Sb.Append(" str");
Sb.AppendLine(i.ToString());
}
Stopwatch.Stop();
ShowCompareResult("StringBuilder", Stopwatch);
} //Elapsing Str1+Str2+... -------------------------------------------
public static void ManualConcatenationExecutionSpeed(int loop)
{
Stopwatch.Restart();
for (int i = ; i < loop; i++)
{
ShowPercentProgress(i, loop);
ResultConcatenation += " str" + i + "\n";
}
Stopwatch.Stop();
ShowCompareResult("str1+str2+...", Stopwatch);
} //Elapsing String.Concat -------------------------------------------
public static void StringConcatExecutionSpeed(int loop)
{
Stopwatch.Restart();
for (int i = ; i < loop; i++)
{
ShowPercentProgress(i, loop);
ResultConcatenation += string.Concat(" str", i, "\n");
}
Stopwatch.Stop();
ShowCompareResult("String.Concat", Stopwatch); } //Elapsing String.Format -------------------------------------------
public static void StringFormatExecutionSpeed(int loop)
{
Stopwatch.Restart();
for (int i = ; i < loop; i++)
{
ShowPercentProgress(i, loop);
ResultConcatenation += string.Format(" str{0}\n", i);
}
Stopwatch.Stop();
ShowCompareResult("String.Format", Stopwatch);
} //Show Compare Result---------------------------------------------
public static void ShowCompareResult(string message, Stopwatch stopwatch)
{
Console.ResetColor();
Console.WriteLine("\r{0}\t{1,9} Millisecond ~={2,3} second ~={3,3} minutes",
message,
Math.Round(stopwatch.Elapsed.TotalMilliseconds),
Math.Round(stopwatch.Elapsed.TotalSeconds),
Math.Round(stopwatch.Elapsed.TotalMinutes));
} //Show processing progress----------------------------------------
static void ShowPercentProgress(int currElementIndex, int totalElementCount)
{
Console.ForegroundColor = ConsoleColor.Green;
int percent = ( * (currElementIndex + )) / totalElementCount;
Console.Write("\r{0}%", percent);
}
}
}