Question

c#里边怎么获得access数据库中某一张表某一字段的类型？

你好，我看了你在知道上的提问，现在我也遇到这个问题了，跪求答案。谢谢！

Answer 1

using System;
using System.Collections.Generic;
using System.Text;
using System.Data.OleDb;
using System.Data;

namespace zjh
{
class Program
{
static void Main(string[] args)
{
OleDbConnection conn = new OleDbConnection();
conn.ConnectionString = "输入连接字符串";
OleDbDataAdapter adp = new OleDbDataAdapter("select * from TableName", conn);
DataTable dt = new DataTable();
conn.Open();
adp.Fill(dt);
conn.Close();
Type t = dt.Columns["列名"].DataType;
Console.WriteLine(t);
Console.ReadLine();
}
}
}

追问

假如某一字段是varchar类型的，怎么获取这个字段的最大字符数呢？

追答

select
o.name as tbname,
c.name as columnname,
t.name as typename,
c.max_length
from sys.tables as o
join sys.columns as c
on o.object_id=c.object_id
join sys.types as t
on c.system_type_id=t.system_type_id
输出这些行数即可