Linq to SQL查询SubQuery

Question

I have a follow up question on the question I asked here

here are all of my Linq query

This is query 1:

var RCode = from a in DbEntity.MobileAssetDowntimeReasonCodes 
            where a.MobileAssetCategoryId.Equals(reasonCode) 
            select new 
            { 
                a.JdeReasonCode 
            };

ReasonCode.DataSource = RCode.ToList();
ReasonCode.DataBind();

this brings a resulting codes that are displayed in DataGrid.

here is Query 2 which also works

var RJDEReasonCode = from a in JDETable.F0005
                                 where
                                   a.DRSY.Equals("00") &&
                                   a.DRDL01 != null &&
                                   (a.DRRT.Equals("W4") ||
                                   a.DRRT.Equals("W5")) &&
                                   a.DRKY.Trim() == "801"
                                 select new
                                 {
                                     CATEGORY_CODE = a.DRRT,
                                     REASON_CODE = a.DRKY,
                                     DESCRIPTION = a.DRDL01
                                 };

But instead of hardcoding "801" I want to pass the result of the query1 to query 2 and display query 2 results in my dataGrid. how do I do that ?

Answer 1

Something like this?

List<string> RCode = DbEntity.MobileAssetDowntimeReasonCodes
    .Where(a=>a.MobileAssetCategoryID.Equals(reasonCode))
    .Select(a=>a.JdeReasonCode).ToList();

var RJDEReasonCode = JDETable.F0005
    .Where(a=>a.DRSY.Equals("00") && a.DRDL01 != null &&
             (a.DRRT.Equals("W4") || a.DRRT.Equals("W5")) &&
              RCode.Any(code => code.Contains(a.DRKY.Trim())))
    .Select(a=>new { CATEGORY_CODE = a.DRRT,
                     REASON_CODE = a.DRKY,
                     DESCRIPTION = a.DRDL01
    });

Uses the Enumerable.Any Method to check if the retrieved RCodes are one of the codes in your F0005 table.

Answer 2

var RJDEReasonCode = from a in JDETable.F0005
                     where
                         a.DRSY.Equals("00") &&
                         a.DRDL01 != null &&
                         (a.DRRT.Equals("W4") ||
                         a.DRRT.Equals("W5")) &&
                         //and use it checking if it contains a.DRKY.Trim() 
                         RCode.Contains(a.DRKY.Trim())
                      select new
                      {
                                     CATEGORY_CODE = a.DRRT,
                                     REASON_CODE = a.DRKY,
                                     DESCRIPTION = a.DRDL01
                      };