结构大修改，改成朴实无华的结构，不过度架构。能跑就行

Assets/Scripts/Common/Utils/Extends/StringExtends.cs

@@ -0,0 +1,11 @@
+namespace NBF
+{
+    public static class StringExtends
+    {
+        public static string GetLastString(this string str)
+        {
+            int lastIndex = str.LastIndexOf('_');
+            return str.Substring(lastIndex + 1);
+        }
+    }
+}