diff --git a/test_xy.c b/test_xy.c
index 5e8ee2b..bc5d1ab 100644
--- a/test_xy.c
+++ b/test_xy.c
@@ -25,11 +25,16 @@ main (int argc, char const *argv[])
   puts(xy_strjoin(6, "楚山横地出，", "汉水接天回。", "冠盖非新里，", "章华即旧台。", "习池风景异，", "归路满尘埃。"));
 
 
-  putb(xy_str_end_with("abcdef", "abcdefg"));
-  putb(xy_str_end_with("abcdef", "def"));
-  putb(xy_str_end_with("abcdef", "bcdef"));
-  putb(xy_str_end_with("abcdef", "abcdef"));
-  putb(xy_str_end_with("abcdef", ""));
+  putb(xy_str_end_with("abcdef", "abcdefg")); // false
+  putb(xy_str_end_with("abcdef", "def"));     // true
+  putb(xy_str_end_with("abcdef", "bcdef"));   // true
+  putb(xy_str_end_with("abcdef", "abcdef"));  // true
+  putb(xy_str_end_with("abcdef", ""));        // true
+
+  puts(xy_str_delete_suffix("abcdefg", "cdef"));  // 不变
+  puts(xy_str_delete_suffix("abcdefg", "cdefgh"));// 不变
+  puts(xy_str_delete_suffix("abcdefg", ""));      // 不变
+  puts(xy_str_delete_suffix("abcdefg", "efg"));   // abcd
 
   xy_success("成功：输出成功内容");
   xy_info("信息: 输出信息内容");
diff --git a/xy.h b/xy.h
index 2a5fd4e..ec5f593 100644
--- a/xy.h
+++ b/xy.h
@@ -301,4 +301,19 @@ xy_str_end_with (const char* str, const char* suffix)
   return true;
 }
 
+
+char*
+xy_str_delete_suffix (const char* str, const char* suffix)
+{
+  char* new = xy_strdup(str);
+  bool yes = xy_str_end_with(str, suffix);
+  if (!yes) return new;
+
+  size_t len1 = strlen(str);
+  size_t len2 = strlen(suffix);
+  char* cur = new + len1 - len2;
+  *cur = '\0';
+  return new;
+}
+
 #endif