之前在和老何谈论他的开源项目Util中使用MySql的过程中发现了官方dapper在转换guid到string时候的一个错误
Error parsing column 0 (ID=6c2adb93-d81a-4fda-8e25-c6e90d4ebaaa - Object)
在官方github提了issue但一直没有给到更新和回复，其实解决方案也是非常简单的，利用dapper的TypeHandler处理下转换的过程即可
public class StringGuidHandler:SqlMapper.TypeHandler<string>
{
public override void SetValue(IDbDataParameter parameter, string value)
{
parameter.Value = value;
} public override string Parse(object value)
{
return value.ToString();
}
}
之后全局加入即可（此处为了方便以console为例)
using Dapper;
using System;
using System.Data.SqlClient; namespace GuidDemo
{
class Program
{
static void Main(string[] args)
{
try
{
SqlMapper.AddTypeHandler(typeof(string), new StringGuidHandler());
string sqlString = "server=192.168.1.3;uid=sa;pwd=demo$;database=demo;";
using (SqlConnection conn = new SqlConnection(sqlString))
{
conn.Open();//打开连接 string strSql = @"SELECT * from Test_002 WHERE Name='sa'"; Test_002 count = conn.QueryFirst<Test_002>(strSql); var testObject=new Test_002(){ID =Guid.NewGuid().ToString(),Name = "b"};
conn.Execute($"insert into Test_002 (Id,Name) values ({testObject.ID},{testObject.Name})"); }
}
catch(Exception e)
{ }
}
}
} using System.Data;
using Dapper; namespace GuidDemo
{
public class StringGuidHandler:SqlMapper.TypeHandler<string>
{
public override void SetValue(IDbDataParameter parameter, string value)
{
parameter.Value = value;
} public override string Parse(object value)
{
return value.ToString();
}
}
}