/StringSwitch-C

Primary LanguageCMIT LicenseMIT

StringSwitch-C

README for strswitch.h

Overview

This project provides a macro-based utility for string matching using switch-case semantics in C. It defines two methods to facilitate efficient string comparisons with cleaner syntax. This header simplifies the process of handling multiple string cases, improving readability and reducing error-prone code.

Features

  • Two implementations: Choose between two methods based on code style and preference.
  • Macro-driven string comparisons: Use familiar switch-case constructs for string matching.
  • Easy-to-read code: Reduces the complexity of repetitive if-else string comparisons.
  • Support for a default case when no string matches.

Usage

First Implementation (Enabled by #if 1)

In this version, you define string pairs using the StringPair_t structure. Each pair consists of an id and a corresponding string. The StrSwitch macro performs string comparisons and evaluates cases based on the id.

Example:

const char *command = "start";

StringPair_t commands[] = {
    {1, "start"},
    {2, "stop"},
    {3, "restart"},
    STRINGPAIR_END
};

StrSwitch(command, commands) {
    StrCase(1, "start") {
        printf("Starting...\n");
        break;
    }
    StrCase(2)
        printf("Stopping...\n");
        break;
    StrCase(3)
        printf("Restarting...\n");
        break;
    StrDefault()
        printf("Unknown command\n");
}

Second Implementation (Enabled by #if 0)

The second version offers an alternative string matching syntax. It uses StrSwitch, StrCase, StrDefault, and StrSwitchEnd macros to simulate a switch-case structure for strings.

Example:

const char *key = "CommandA";

StrSwitch(key) {

    StrCase("CommandA")
    StrCase("CommandB") {
        printf("match str %s\n", key);
        break;
    }

    StrDefault() {
        printf("match str unknown\n");
        break;
    }
    
} StrSwitchEnd

中文

概述

该项目提供了基于宏定义的工具，用于在 C 语言中实现类似 switch-case 的字符串匹配。此头文件定义了两种方法，简化了字符串匹配的过程，使代码更清晰、更易读，并减少了重复性代码的出错风险。

功能特点

  • 两种实现方式：可以根据代码风格和需求选择不同的实现。
  • 基于宏的字符串比较：使用类似 switch-case 的语法结构进行字符串匹配。
  • 代码清晰易读：减少了复杂的 if-else 语句。
  • 支持默认情况：当没有匹配的字符串时执行默认操作。

用法

第一种实现方式（通过 #if 1 启用）

在此实现中，通过 StringPair_t 结构体定义字符串对。每对包含一个 id 和对应的字符串。StrSwitch 宏用于进行字符串比较，并根据 id 匹配对应的 case。

示例：

const char *command = "start";

StringPair_t commands[] = {
    {1, "start"},
    {2, "stop"},
    {3, "restart"},
    STRINGPAIR_END
};

StrSwitch(command, commands) {
    StrCase(1, "start") {
        printf("Starting...\n");
        break;
    }
    StrCase(2)
        printf("Stopping...\n");
        break;
    StrCase(3)
        printf("Restarting...\n");
        break;
    StrDefault()
        printf("Unknown command\n");
}

第二种实现方式（通过 #if 0 启用）

此实现方式提供了另一种字符串匹配的语法。通过 StrSwitch、StrCase、StrDefault 和 StrSwitchEnd 宏来模拟字符串的 switch-case 结构。

示例：

const char *key = "CommandA";

StrSwitch(key) {

    StrCase("CommandA")
    StrCase("CommandB") {
        printf("match str %s\n", key);
        break;
    }

    StrDefault() {
        printf("match str unknown\n");
        break;
    }
    
} StrSwitchEnd

This README provides a detailed guide on how to use the two string-switch implementations, including both Chinese and English documentation.