diff --git a/src/WCTDataMiner.Core/Parsers/PlossParser.cs b/src/WCTDataMiner.Core/Parsers/PlossParser.cs
index f8e13ed..9821a9b 100644
--- a/src/WCTDataMiner.Core/Parsers/PlossParser.cs
+++ b/src/WCTDataMiner.Core/Parsers/PlossParser.cs
@@ -29,47 +29,55 @@ public class PlossParser : IParser<PlossRecord>
         RegexOptions.Compiled
     );
 
+    /// <summary>
+    /// 匹配类型枚举
+    /// </summary>
+    public enum MatchType { None, Header, Fod, Legacy }
+
+    /// <summary>
+    /// 单次匹配结果（避免重复正则匹配）
+    /// </summary>
+    public (MatchType Type, Match Match) TryMatch(string line)
+    {
+        var headerMatch = HeaderPattern.Match(line);
+        if (headerMatch.Success)
+            return (MatchType.Header, headerMatch);
+
+        var fodMatch = FodPattern.Match(line);
+        if (fodMatch.Success)
+            return (MatchType.Fod, fodMatch);
+
+        var legacyMatch = LegacyPattern.Match(line);
+        if (legacyMatch.Success)
+            return (MatchType.Legacy, legacyMatch);
+
+        return (MatchType.None, Match.Empty);
+    }
+
     /// <summary>
     /// 判断是否可以解析该行（任意一行）
     /// </summary>
-    public bool CanParse(string line) =>
-        HeaderPattern.IsMatch(line) || FodPattern.IsMatch(line) || LegacyPattern.IsMatch(line);
+    public bool CanParse(string line) => TryMatch(line).Type != MatchType.None;
 
     /// <summary>
     /// 判断是否为多行记录的起始行（header行）
     /// </summary>
-    public bool IsMultiLineStart(string line) => HeaderPattern.IsMatch(line);
+    public bool IsMultiLineStart(string line) => TryMatch(line).Type == MatchType.Header;
 
     /// <summary>
     /// 单行解析（兼容旧格式）
     /// </summary>
     public ParseResult<PlossRecord> Parse(string line, Guid scenarioId)
     {
-        // 尝试匹配旧格式
-        var legacyMatch = LegacyPattern.Match(line);
-        if (legacyMatch.Success)
-        {
-            return ParseLegacyFormat(legacyMatch, scenarioId);
-        }
+        var (type, match) = TryMatch(line);
 
-        // 尝试匹配第二行（新格式）
-        var fodMatch = FodPattern.Match(line);
-        if (fodMatch.Success)
+        return type switch
         {
-            return ParseFodLine(fodMatch, scenarioId);
-        }
-
-        // 尝试匹配第一行
-        var headerMatch = HeaderPattern.Match(line);
-        if (headerMatch.Success)
-        {
-            return ParseHeaderLine(headerMatch, scenarioId);
-        }
-
-        return ParseResult<PlossRecord>.Failure(
-            "FORMAT_MISMATCH",
-            "Line does not match Ploss pattern"
-        );
+            MatchType.Legacy => ParseLegacyFormat(match, scenarioId),
+            MatchType.Fod => ParseFodLine(match, scenarioId),
+            MatchType.Header => ParseHeaderLine(match, scenarioId),
+            _ => ParseResult<PlossRecord>.Failure("FORMAT_MISMATCH", "Line does not match Ploss pattern")
+        };
     }
 
     /// <summary>
@@ -77,7 +85,7 @@ public class PlossParser : IParser<PlossRecord>
     /// </summary>
     public ParseResult<PlossRecord>? ParseMultiLine(string[] lines, Guid scenarioId)
     {
-        if (lines.Length < 2)
+        if (lines.Length < 2 || lines[0] == null || lines[1] == null)
             return null;
 
         var headerMatch = HeaderPattern.Match(lines[0].Trim());