C# List转SqlServer、MySql中in字符串

var oneList = new List<string>
{
"1",
"2",
"3"
};
var oneString = string.Join("'" + ",'", oneList.ToArray());

var twoList = new List<int>
{
1,
2,
3
};
var twoString = string.Join(",", twoList.ToArray());

Console.WriteLine();
Console.WriteLine(oneString);
Console.WriteLine();
Console.WriteLine(twoString);
Console.ReadKey();

输出结果