diff --git a/lsp-server/src/main.cpp b/lsp-server/src/main.cpp
index 6f78723..76c1110 100644
--- a/lsp-server/src/main.cpp
+++ b/lsp-server/src/main.cpp
@@ -8,7 +8,7 @@
 
 int main(int argc, char* argv[])
 {
-    lsp::utils::ArgsParser& args_parser = lsp::utils::ArgsParser::GetInstance();
+    lsp::utils::ArgsParser& args_parser = lsp::utils::ArgsParser::Instance();
     auto& config = args_parser.Parse(argc, argv);
 
     if (config.show_help)
diff --git a/lsp-server/src/service/base/bootstrap.cpp b/lsp-server/src/service/base/bootstrap.cpp
index a1694b9..cfd3911 100644
--- a/lsp-server/src/service/base/bootstrap.cpp
+++ b/lsp-server/src/service/base/bootstrap.cpp
@@ -15,7 +15,7 @@ namespace lsp::service
     {
         spdlog::info("Registering LSP services...");
 
-        auto& config = utils::ArgsParser::GetInstance().GetConfig();
+        auto& config = utils::ArgsParser::Instance().GetConfig();
         std::shared_ptr<EventBus> event_bus = std::make_shared<EventBus>();
         std::shared_ptr<Document> document = std::make_shared<Document>(event_bus);
         std::shared_ptr<Parser> parser = std::make_shared<Parser>(event_bus);
diff --git a/lsp-server/src/utils/args_parser.cpp b/lsp-server/src/utils/args_parser.cpp
index 00eb57d..61997e8 100644
--- a/lsp-server/src/utils/args_parser.cpp
+++ b/lsp-server/src/utils/args_parser.cpp
@@ -5,7 +5,7 @@
 
 namespace lsp::utils
 {
-    ArgsParser& ArgsParser::GetInstance()
+    ArgsParser& ArgsParser::Instance()
     {
         static ArgsParser instance;
         return instance;
diff --git a/lsp-server/src/utils/args_parser.hpp b/lsp-server/src/utils/args_parser.hpp
index 06c5504..581ad00 100644
--- a/lsp-server/src/utils/args_parser.hpp
+++ b/lsp-server/src/utils/args_parser.hpp
@@ -19,7 +19,7 @@ namespace lsp::utils
     public:
         ArgsParser(const ArgsParser&) = delete;
         ArgsParser& operator=(const ArgsParser&) = delete;
-        static ArgsParser& GetInstance();
+        static ArgsParser& Instance();
 
         const ServerConfig& Parse(int argc, char* argv[]);
         const ServerConfig& GetConfig() const;
diff --git a/lsp-server/src/utils/string.cpp b/lsp-server/src/utils/string.cpp
index 57b4316..81415be 100644
--- a/lsp-server/src/utils/string.cpp
+++ b/lsp-server/src/utils/string.cpp
@@ -9,34 +9,104 @@ namespace lsp::utils
         if (first == std::string::npos)
             return "";
         size_t last = str.find_last_not_of(" \t\n\r");
-        return str.substr(first, (last - first + 1));
+        return str.substr(first, last - first + 1);
     }
 
     std::string ToLower(const std::string& str)
     {
         std::string result = str;
-        std::transform(result.begin(), result.end(), result.begin(), ::tolower);
+        std::transform(result.begin(), result.end(), result.begin(), [](unsigned char c) { return std::tolower(c); });
         return result;
     }
 
-    bool StartsWithIgnoreCase(const std::string& str, const std::string& prefix)
+    std::string ToUpper(const std::string& str)
+    {
+        std::string result = str;
+        std::transform(result.begin(), result.end(), result.begin(), [](unsigned char c) { return std::toupper(c); });
+        return result;
+    }
+
+    bool StartsWith(const std::string& str, const std::string& prefix)
+    {
+        if (prefix.size() > str.size())
+            return false;
+        return str.compare(0, prefix.size(), prefix) == 0;
+    }
+
+    bool EndsWith(const std::string& str, const std::string& suffix)
+    {
+        if (suffix.size() > str.size())
+            return false;
+        return str.compare(str.size() - suffix.size(), suffix.size(), suffix) == 0;
+    }
+
+    // ==================== 大小写不敏感比较 ====================
+    bool IEquals(const std::string& a, const std::string& b)
+    {
+        if (a.size() != b.size())
+            return false;
+
+        return std::equal(a.begin(), a.end(), b.begin(), [](unsigned char ca, unsigned char cb) {
+            return std::tolower(ca) == std::tolower(cb);
+        });
+    }
+
+    bool IStartsWith(const std::string& str, const std::string& prefix)
     {
         if (prefix.size() > str.size())
             return false;
 
         for (size_t i = 0; i < prefix.size(); ++i)
-            if (std::tolower(str[i]) != std::tolower(prefix[i]))
+        {
+            if (std::tolower(static_cast<unsigned char>(str[i])) !=
+                std::tolower(static_cast<unsigned char>(prefix[i])))
                 return false;
+        }
         return true;
     }
 
-    bool StartsWith(const std::string& str, const std::string& prefix, bool ignoreCase)
+    bool IEndsWith(const std::string& str, const std::string& suffix)
     {
-        if (ignoreCase)
-            return StartsWithIgnoreCase(str, prefix);
-
-        if (prefix.size() > str.size())
+        if (suffix.size() > str.size())
             return false;
-        return str.compare(0, prefix.size(), prefix) == 0;
+
+        size_t offset = str.size() - suffix.size();
+        for (size_t i = 0; i < suffix.size(); ++i)
+        {
+            if (std::tolower(static_cast<unsigned char>(str[offset + i])) !=
+                std::tolower(static_cast<unsigned char>(suffix[i])))
+                return false;
+        }
+        return true;
+    }
+
+    int ICompare(const std::string& a, const std::string& b)
+    {
+        size_t min_len = std::min(a.size(), b.size());
+
+        for (size_t i = 0; i < min_len; ++i)
+        {
+            int ca = std::tolower(static_cast<unsigned char>(a[i]));
+            int cb = std::tolower(static_cast<unsigned char>(b[i]));
+
+            if (ca != cb)
+                return ca - cb;
+        }
+
+        // 长度不同
+        if (a.size() < b.size())
+            return -1;
+        if (a.size() > b.size())
+            return 1;
+
+        return 0;
+    }
+
+    size_t IHash(const std::string& str)
+    {
+        size_t hash = 0;
+        for (unsigned char c : str)
+            hash = hash * 31 + std::tolower(c);
+        return hash;
     }
 }
diff --git a/lsp-server/src/utils/string.hpp b/lsp-server/src/utils/string.hpp
index bed1bd1..108ecc1 100644
--- a/lsp-server/src/utils/string.hpp
+++ b/lsp-server/src/utils/string.hpp
@@ -4,8 +4,44 @@
 
 namespace lsp::utils
 {
+    // ==================== 字符串工具 ====================
     std::string Trim(const std::string& str);
     std::string ToLower(const std::string& str);
-    bool StartsWith(const std::string& str, const std::string& prefix, bool ignoreCase = true);
-    bool StartsWithIgnoreCase(const std::string& str, const std::string& prefix);
+    std::string ToUpper(const std::string& str);
+
+    // ==================== 大小写敏感比较 ====================
+    bool StartsWith(const std::string& str, const std::string& prefix);
+    bool EndsWith(const std::string& str, const std::string& suffix);
+
+    // ==================== 大小写不敏感比较 ====================
+    bool IEquals(const std::string& a, const std::string& b);
+    bool IStartsWith(const std::string& str, const std::string& prefix);
+    bool IEndsWith(const std::string& str, const std::string& suffix);
+    int ICompare(const std::string& a, const std::string& b);
+    size_t IHash(const std::string& str);
+
+    // ==================== STL 容器比较器 ====================
+    struct IHasher
+    {
+        size_t operator()(const std::string& key) const
+        {
+            return IHash(key);
+        }
+    };
+
+    struct IEqualTo
+    {
+        bool operator()(const std::string& a, const std::string& b) const
+        {
+            return IEquals(a, b);
+        }
+    };
+
+    struct ILess
+    {
+        bool operator()(const std::string& a, const std::string& b) const
+        {
+            return ICompare(a, b) < 0;
+        }
+    };
 }