doc: update docs/cs.md (#514)

jaywcjlove · Feb 8, 2024 · c60876d · c60876d
1 parent e391ce4
commit c60876d
Showing 1 changed file with 11 additions and 0 deletions.
diff --git a/docs/cs.md b/docs/cs.md
@@ -289,6 +289,17 @@ Console.WriteLine(multiLine); // => Content begin "Hello World!" /\n<>"" end.
 
 ### 字符串操作
 
+#### 字符串判空
+
+```cs
+string name; //空引用
+string gender = ""; //空值
+
+// 使用 string.IsNullOrEmpty(字符串) 方法，返回 bool 型
+Console.WriteLine(string.IsNullOrEmpty(name)); //输出 true
+Console.WriteLine(string.IsNullOrEmpty(gender)); // 输出 true
+```
+
 #### 字符串分割
 
 ```cs