diff --git a/Falcon.SugarApi/StringExtend.cs b/Falcon.SugarApi/StringExtend.cs
index d165a8b..41ee913 100644
--- a/Falcon.SugarApi/StringExtend.cs
+++ b/Falcon.SugarApi/StringExtend.cs
@@ -12,19 +12,21 @@ namespace Falcon.SugarApi
         /// </summary>
         /// <param name="str">字符串</param>
         /// <returns>空或null为True，否则False</returns>
-        public static bool IsNullOrEmpty(this string str) => str == null || string.IsNullOrEmpty(str);
+        public static bool IsNullOrEmpty(this string? str) => str == null || string.IsNullOrEmpty(str);
         /// <summary>
         /// 字符串是否不为空或null
         /// </summary>
         /// <param name="str">字符串</param>
         /// <returns>与IsNullOrEmpty相反</returns>
-        public static bool IsNotNullOrEmpty(this string str) => !str.IsNullOrEmpty();
+        public static bool IsNotNullOrEmpty(this string? str) => !str.IsNullOrEmpty();
 
         /// <summary>
         /// 使用全角半角的逗号句号和分号分割字符串。
         /// </summary>
         /// <param name="str">要分割的字符串</param>
+        /// <param name="splitChars"></param>
         /// <returns>字符串数组。当str为null时返回空数组</returns>
-        public static string[] SplitStr(this string? str) => str == null ? Array.Empty<string>() : str.Split(new char[] { ',', '，', ';', '；', '.', '。' }, StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+        public static string[] SplitStr(this string? str, params char[] splitChars)
+            => str.IsNullOrEmpty() ? Array.Empty<string>() : str.Split(splitChars.Length == 0 ? new char[] { ',', '，', ';', '；', '.', '。' } : splitChars, StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
     }
 }