前言
在C#編程中字符串拼接是一種常見且基礎的操作，廣泛應用于各種場景，如動態生成SQL查詢、構建日志信息、格式化用戶顯示內容等。然而，不同的字符串拼接方式在性能和內存使用上可能存在顯著差異。今天咱們一起來看看在C#中字符串拼接的常見6種方式及其使用BenchmarkDotNet進行性能分析對比。
BenchmarkDotNet
BenchmarkDotNet是一個基于.NET開源、功能全面、易于使用的性能基準測試框架，它為.NET開發者提供了強大的性能評估和優化能力。通過自動化測試、多平臺支持、高級統計分析和自定義配置等特性，BenchmarkDotNet幫助開發者更好地理解和優化軟件系統的性能表現。
拼接基礎數據
private const int IterationCount = 1000;
private const string StringPart1 = "追逐時光者";
private const string StringPart2 = "DotNetGuide";
private const string StringPart3 = "DotNetGuide技術社區";
private readonly string[] _stringPartsArray = { "追逐時光者", "DotNetGuide", "DotNetGuide技術社區" };
+操作符
/// <summary>
/// 使用 + 操作符拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string PlusOperator()
{
string result = StringPart1 + " " + StringPart2 + " " + StringPart3;
return result;
}
$內插字符串
/// <summary>
/// 使用 $ 內插字符串拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string InterpolatedString()
{
string result = $"{StringPart1} {StringPart2} {StringPart3}";
return result;
}
String.Format
/// <summary>
/// 使用string.Format()拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringFormat()
{
string result = string.Format("{0} {1} {2}", StringPart1, StringPart2, StringPart3);
return result;
}
String.Concat
/// <summary>
/// 使用string.Concat()拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringConcat()
{
string result = string.Concat(StringPart1, " ", StringPart2, " ", StringPart3);
return result;
}
String.Join
/// <summary>
/// 使用string.Join()拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringJoin()
{
string result = string.Join(" ", _stringPartsArray);
return result;
}
StringBuilder
Append拼接字符串
/// <summary>
/// 使用StringBuilder.Append拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringBuilderAppend()
{
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append(StringPart1);
stringBuilder.Append(" ");
stringBuilder.Append(StringPart2);
stringBuilder.Append(" ");
stringBuilder.Append(StringPart3);
return stringBuilder.ToString();
}
AppendFormat拼接字符串
/// <summary>
/// 使用StringBuilder.AppendFormat拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringBuilderAppendFormat()
{
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.AppendFormat("{0} {1} {2}", StringPart1, StringPart2, StringPart3);
return stringBuilder.ToString();
}
性能基準對比測試完整代碼
咱們分別以少量字符串拼接和大量字符串拼接為例，進行性能基準對比測試：
說明：
- Gen0: 第 0 代 GC 每 1000 次操作收集一次。
- Gen1: 第 1 代 GC 每 1000 次操作收集一次。
- Gen2: 第 2 代 GC 每 1000 次操作收集一次。
- Allocated: 每次操作分配的內存（僅托管內存，包含所有內容，1KB = 1024B）。
少量字符串拼接
using BenchmarkDotNet.Attributes;
using System.Text;
namespace BenchmarkDotNetExercise
{
[MemoryDiagnoser]//記錄內存分配情況
public class StringConcatenationBenchmark
{
private const int IterationCount = 1000;
private const string StringPart1 = "追逐時光者";
private const string StringPart2 = "DotNetGuide";
private const string StringPart3 = "DotNetGuide技術社區";
private readonly string[] _stringPartsArray = { "追逐時光者", "DotNetGuide", "DotNetGuide技術社區" };
#region 少量字符串拼接
/// <summary>
/// 使用 + 操作符拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string PlusOperator()
{
string result = StringPart1 + " " + StringPart2 + " " + StringPart3;
return result;
}
/// <summary>
/// 使用 $ 內插字符串拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string InterpolatedString()
{
string result = $"{StringPart1} {StringPart2} {StringPart3}";
return result;
}
/// <summary>
/// 使用string.Format()拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringFormat()
{
string result = string.Format("{0} {1} {2}", StringPart1, StringPart2, StringPart3);
return result;
}
/// <summary>
/// 使用string.Concat()拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringConcat()
{
string result = string.Concat(StringPart1, " ", StringPart2, " ", StringPart3);
return result;
}
/// <summary>
/// 使用string.Join()拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringJoin()
{
string result = string.Join(" ", _stringPartsArray);
return result;
}
/// <summary>
/// 使用StringBuilder.Append拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringBuilderAppend()
{
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append(StringPart1);
stringBuilder.Append(" ");
stringBuilder.Append(StringPart2);
stringBuilder.Append(" ");
stringBuilder.Append(StringPart3);
return stringBuilder.ToString();
}
/// <summary>
/// 使用StringBuilder.AppendFormat拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string StringBuilderAppendFormat()
{
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.AppendFormat("{0} {1} {2}", StringPart1, StringPart2, StringPart3);
return stringBuilder.ToString();
}
#endregion
}
}
大量字符串拼接
using BenchmarkDotNet.Attributes;
using System.Text;
namespace BenchmarkDotNetExercise
{
[MemoryDiagnoser]//記錄內存分配情況
public class StringConcatenationBenchmark
{
private const int IterationCount = 1000;
private const string StringPart1 = "追逐時光者";
private const string StringPart2 = "DotNetGuide";
private const string StringPart3 = "DotNetGuide技術社區";
private readonly string[] _stringPartsArray = { "追逐時光者", "DotNetGuide", "DotNetGuide技術社區" };
#region 大量字符串拼接
/// <summary>
/// 使用 + 操作符拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string BigDataPlusOperator()
{
string result = string.Empty;
for (int i = 0; i < IterationCount; i++)
{
result += StringPart1 + " " + StringPart2 + " " + StringPart3;
}
return result;
}
/// <summary>
/// 使用StringBuilder.Append拼接字符串
/// </summary>
/// <returns></returns>
[Benchmark]
public string BigDataStringBuilderAppend()
{
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < IterationCount; i++)
{
stringBuilder.Append(StringPart1);
stringBuilder.Append(" ");
stringBuilder.Append(StringPart2);
stringBuilder.Append(" ");
stringBuilder.Append(StringPart3);
}
return stringBuilder.ToString();
}
#endregion
}
}
該文章在 2025/2/13 9:07:36 編輯過
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