c# 如何将日期和字符串拼接起来

用C# 做了小工具，点击按钮 备份SQL表。
DateTime dt = DateTime.Now;
string ddate = dt.ToString("yyMMdd");
string sql = "select * into rdrecord10 '" + ddate +"' from rdrecord10 "; //备份表

但是报错。“211209”附近有语法错误。

空格删掉，引号也删掉，语法是
select * into 表名称1 from 表名2

string sql = "select * into rdrecord10" + ddate +" from rdrecord10 "; //备份表

有帮助麻烦点下【采纳该答案】

不需要单引号，把2边的单引号删除。

```c#
查看一下SQLService语法
    SELECT column_name(s)
INTO new_table_name [IN externaldatabase] 
FROM old_tablename

new_table_name 是新表名  
原本的你的写法：string sql = "select * into rdrecord10 '" + ddate +"' from rdrecord10 "; //备份表
拼接后：select * into rdrecord10 '211209' from rdrecord10   语法错误

改成：string sql = "select * into rdrecord10_"+ddate +" from rdrecord10 "; //备份表
   或：string sql = $"select * into rdrecord10_{DateTime.Now:yyMMdd} from rdrecord10 "; //备份表
拼接后：select * into rdrecord10_211209 from rdrecord10 

这样语法是正确的

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