找不到用于实现部分方法声明的定义声明 [英] No defining declaration found for implementing declaration of partial method

问题描述

你好


我是linq的新手，并且正在使用"LINQ To Sql"教程系列，因此我使用了以下代码来更新
的电话号码
客户表(示例1)，然后添加一个类并将其命名为"customer.cs"(示例2)

用于防止将虚假电话号码添加到我们的数据库中.

现在，当我调试程序时，出现如下错误(示例3)，

请帮忙，实际上是什么问题，我不知道如何定义局部类

我只知道该类应与northwind.desiner.cs中的客户"一起使用.

在此先谢谢您.


范例1:

Hello


I am new to linq and I am using ‘LINQ To Sql’ Tutorial Series , I used the code like below for updating the phone number of

customers table (sample 1) and then add a class and named it "customer.cs" (sample 2)

for preventing bogus phone numbers from being added into our database.

Now when I debug the program I take the error like below (sample 3) ,

please help what is the problem actually I don''t know how I have to define partial class

just I know this class should works with "customer" in northwind.desiner.cs.

Thanks in advanced.


Sample 1:

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

namespace WebApplication1
{
    public partial class _Default : System.Web.UI.Page
    {
        

        protected void Page_Load(object sender, EventArgs e)
        {
           NorthwindDataContext northwind=new NorthwindDataContext();
           Customer mycustumer = northwind.Customers.Single(c => c.CompanyName == "B''s Beverages");
           mycustumer.Phone = "999";
           northwind.SubmitChanges();
           



        }
    }
}

示例2:

sample 2:

using System;
using System.Data;
using System.Configuration;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Text.RegularExpressions;


namespace WebApplication1
{
    public partial class customer
    {
        partial void onphonechanging(string value)
        {
            Regex phoneNumber = new Regex(@"^[2-9]\d{2}-\d{3}-\d{4}$");

            if (phoneNumber.IsMatch(value) == false)
            {
                throw new Exception("not valid");
            }

            
        }
    }
}

推荐答案

)； 如果(phoneNumber.IsMatch(value)==否) { 抛出新的Exception(无效"); } } } }

"); if (phoneNumber.IsMatch(value) == false) { throw new Exception("not valid"); } } } }

只需注释部分客户，并执行以下操作即可工作

1.转到您的* .dbml文件

2.右键单击客户"类，然后选择查看代码"，然后将您的部分验证类放在此处，以下是我尝试过的示例验证

Just comment your partial class customer and do the followings and should work

1.Go to your *.dbml file

2.Right click on the "customer" class and select "View Code" and put your partial validation class there, following is the sample validation i have tried

namespace CSUTOMER_PHONE_NUMBER
{
    partial class Customer
    {
        partial void OnPhoneChanging(string value)
        {
            if (value.Length ==1)
            throw new System.Exception ("not valid");
        }
    }
}

而当您设置电话号码的值时，它会起作用

and when you set the value for the phone number it works

try
           {
               DataClasses1DataContext db = new DataClasses1DataContext();
               Customer mycustumer = db.Customers.Single(c => c.CompanyName == "B''s Beverages");
               mycustumer.Phone = "1";
               db.SubmitChanges();

               MessageBox.Show("OK");
           }
           catch (Exception ex)
           {
               MessageBox.Show(ex.Message);

           }

希望对您有帮助

Hope this helps

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