指定的强制转换不是有效的C#实体框架

本文关键字:有效 实体 框架 转换 | 更新日期: 2023-09-27 18:00:46

嗨,我一直在获取此指定强制转换在我的代码中无效,但当我连接到备份数据库时,我没有获取指定强制转换无效错误。我不知道发生了什么事。

同样,这段代码在一个数据库上运行得很好,并在另一个数据库中给了我错误。

我的控制器

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Data.Linq.SqlClient;
using System.Text.RegularExpressions;
using MvcPaging;
using lookups.Models;
using lookups.Helpers;

namespace lookups.Controllers
{
public class MPController : Controller
{
    // GET: /Lookups/
    public LpAppsDataDataContext db = new LpAppsDataDataContext();
    public const int DefaultPageSize = 30;

    //get MP Data
         if (countSpace == 1 && v.Count(char.IsLetter) > 3)
                            {
                                if (SqlString.CheckStringForComma(v))
                                {
                                    mpq = db.mps
                                         .Where(c => c.NAME_LAST.ToLower().Contains(SqlString.GetSplitCommaString(v.ToLower(), 0))).OrderBy(c => c.NAME_LAST).ThenBy(f => f.NAME_FIRST);
                                }
                                else
                                {
                                    mpq = db.mps
                                       .Where(c => c.NAME_LAST.ToLower().Contains(SqlString.GetSplitString(v.ToLower(), 1)) || c.NAME_LAST.Contains(SqlString.GetSplitString(v.ToLower(), 0))).OrderBy(c => c.NAME_LAST).ThenBy(f => f.NAME_FIRST);
                                }
                            }
                            else
                            {
                                mpq = db.mps
                                       .Where(c => c.NAME_L
                ViewBag.count = mpq.Count();
            }
        }
        else { ViewBag.count = 0; }
        @ViewBag.col = "Unclaimed Pensions";
        return View(mpq.ToPagedList(currentPageIndex, DefaultPageSize));
    }
}
}

我的型号

[global::System.Data.Linq.Mapping.TableAttribute(Name = "dbo.mp")]
public partial class mp
{
    private string _COMPANY;
    private string _STATE;
    private System.Nullable<System.DateTime> _DOPT;
    private string _SP_STATE;
    private string _PRT_NAME;
    private string _NAME_LAST;
    private string _NAME_FIRST;
    private string _LASTADDRESS;
    private System.Nullable<double> _ID;
    private System.Nullable<System.DateTime> _DATE;
    private string _PLAN_TYPE;
    public mp()
    {
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_COMPANY", DbType = "NVarChar(255)")]
    public string COMPANY
    {
        get
        {
            return this._COMPANY;
        }
        set
        {
            if ((this._COMPANY != value))
            {
                this._COMPANY = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_STATE", DbType = "NVarChar(255)")]
    public string STATE
    {
        get
        {
            return this._STATE;
        }
        set
        {
            if ((this._STATE != value))
            {
                this._STATE = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_DOPT", DbType = "DateTime")]
    public System.Nullable<System.DateTime> DOPT
    {
        get
        {
            return this._DOPT;
        }
        set
        {
            if ((this._DOPT != value))
            {
                this._DOPT = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_SP_STATE", DbType = "NVarChar(255)")]
    public string SP_STATE
    {
        get
        {
            return this._SP_STATE;
        }
        set
        {
            if ((this._SP_STATE != value))
            {
                this._SP_STATE = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_PRT_NAME", DbType = "NVarChar(255)")]
    public string PRT_NAME
    {
        get
        {
            return this._PRT_NAME;
        }
        set
        {
            if ((this._PRT_NAME != value))
            {
                this._PRT_NAME = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_NAME_LAST", DbType = "NVarChar(255)")]
    public string NAME_LAST
    {
        get
        {
            return this._NAME_LAST;
        }
        set
        {
            if ((this._NAME_LAST != value))
            {
                this._NAME_LAST = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_NAME_FIRST", DbType = "NVarChar(255)")]
    public string NAME_FIRST
    {
        get
        {
            return this._NAME_FIRST;
        }
        set
        {
            if ((this._NAME_FIRST != value))
            {
                this._NAME_FIRST = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_LASTADDRESS", DbType = "NVarChar(255)")]
    public string LASTADDRESS
    {
        get
        {
            return this._LASTADDRESS;
        }
        set
        {
            if ((this._LASTADDRESS != value))
            {
                this._LASTADDRESS = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_ID", DbType = "Float")]
    public System.Nullable<double> ID
    {
        get
        {
            return this._ID;
        }
        set
        {
            if ((this._ID != value))
            {
                this._ID = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_DATE", DbType = "DateTime")]
    public System.Nullable<System.DateTime> DATE
    {
        get
        {
            return this._DATE;
        }
        set
        {
            if ((this._DATE != value))
            {
                this._DATE = value;
            }
        }
    }
    [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_PLAN_TYPE", DbType = "NVarChar(255)")]
    public string PLAN_TYPE
    {
        get
        {
            return this._PLAN_TYPE;
        }
        set
        {
            if ((this._PLAN_TYPE != value))
            {
                this._PLAN_TYPE = value;
            }
        }
    }
}

StackTrace

Line 257:            @ViewBag.col = "Unclaimed Pensions";
Line 258:
Line 259:            return View(mpq.ToPagedList(currentPageIndex,      DefaultPageSize));
Line 260:        }
Line 261:
Stack Trace: 

[InvalidCastException: Specified cast is not valid.]
 System.Data.SqlClient.SqlBuffer.get_Double() +51
System.Data.SqlClient.SqlDataReader.GetDouble(Int32 i) +62
 Read_mp(ObjectMaterializer`1 ) +2057
 System.Data.Linq.SqlClient.ObjectReader`2.MoveNext() +32
   System.Collections.Generic.List`1.InsertRange(Int32 index, IEnumerable`1 collection) +392
   System.Collections.Generic.List`1.AddRange(IEnumerable`1 collection) +10
   MvcPaging.PagedList`1..ctor(IQueryable`1 source, Int32 index, Int32    pageSize, Nullable`1 totalCount) +2014
   MvcPaging.PagingExtensions.ToPagedList(IQueryable`1 source, Int32 pageIndex, Int32 pageSize, Nullable`1 totalCount) +134
   lookups.Controllers.MPController.Mp(Nullable`1 page, String sortOrder) in 

指定的强制转换不是有效的C#实体框架

将备份数据库与不起作用的数据库进行比较,特别是ID列。确保它们与类型(浮点)和可为NULL的能力匹配(NULL)。

抛出的异常表明其中一列(类型为"double")与模型不匹配。

"mp"表上的ID列是模型中唯一的双列。

在SQL Server Developer 2019中,我使用sys表创建了一个SQL脚本,以确定SQL Server认为每列的类型。

select
    obj.name as [Table]
    , col.name as [Column]
    , case
        when type.[precision] > 0 and type.scale = 0 then type.name + '(' + CONVERT(nvarchar(8), type.precision) + ')'
        when type.[precision] > 0 and type.scale > 0 then type.name + '(' + CONVERT(nvarchar(8), type.precision) + ',' + CONVERT(nvarchar(8), type.scale) + ')'
        else type.name end as [FullType]
from
    sys.objects as [obj]
    inner join sys.columns as [col]
        on obj.object_id = col.object_id
    inner JOIN sys.types as [type]
        on col.system_type_id = type.system_type_id
where 
    obj.type = N'U'

然后,我可以在通用表表达式(CTE)或其他类似结构中使用脚本来过滤特定列。