how to use join with linq? RSS

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  mehtapratik

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  how to use join with linq?

  Mar 03, 2009 11:57 AM | LINK

   hi everyone, I am new to linq and i have some difficulty with join.

         I have two  tables:

        1) UserPermission - (columns: permissionid, fkmoduleid, permissionname)
  

        2) module (columns: pkmoduleid, modulename)

       and i have added two differenct linq to sql classes for above. and now i want to use join on the moduleid so that when i make method it returns list with the all the columns of userpermission with modulename of module table. currently i have written following code without join.

        public List<BWS.DB.DAL.UserPermission> GetUserPermissionList(Int32 CompanyID, Int32 UserTypeID)
          {
              UserPermissionsDataDataContext objDataContext = new UserPermissionsDataDataContext();
               return objDataContext.UserPermissions.Where(UP => UP.CompanyId == CompanyID && UP.UserTypeID == UserTypeID).ToList();
          }
          public Int32 Update(List<BWS.DB.DAL.UserPermission> PermissionList)
          {
              try
              {
                  UserPermissionsDataDataContext objDataContext = new UserPermissionsDataDataContext();
                 
                  for (int i = 0; i < PermissionList.Count; i++)
                  {
                      UserPermission temp =(objDataContext.UserPermissions.First(PL => PL.id == PermissionList[i].id));
                      PropertyInfo[] properties = temp.GetType().GetProperties();
                      foreach (PropertyInfo property in properties)
                      {
                          if (null != property.GetSetMethod())
                          {
                              MappingProvider.MapProperties(PermissionList[i], temp, property);
                          }
                      }
                      objDataContext.SubmitChanges();
                  }
                  return 1;
              }
              catch
              {
                  return -1;
              }
          }
  

   Please suggest some easy way so that the update operation is also simple. Thanks
  

        
  

      
  

   

  Pratik Mehta
  Espirit Softwares Pvt. Ltd.
  India.
• 

  HarshBardhan

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  Re: how to use join with linq?

  Mar 03, 2009 12:05 PM | LINK

   Hi,

  Check these links.

  http://code.msdn.microsoft.com/LinqtoSQLJoinExample

  http://code.msdn.microsoft.com/LinqtoSQLJoinExample/Release/ProjectReleases.aspx?ReleaseId=58
  

  Mark as answer if this post answered your question.
  
  Harsh Bardhan
• 

  Hemant@Silve...

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  Re: Re: how to use join with linq?

  Mar 05, 2009 04:24 AM | LINK

  Define the association(PK-Fk relation ) between tables in database or set associationmapping  in datamodel design.

  once proper association is created you will get module table as an property of userpermission entitiy. No need to loop in to get master table.

  you can access as

  from userPerm in userPermission

   select userPerm.Module.moduleName

   

   

  Mark as answer if this answered your query
  
  Hemant Patidar
  Diaspark Inc., Indore