How to combine multiple table using Linq? - entity-framework

Question

public class JobDescription
{
public int JobDescriptionID { get; set; }
//
public virtual List<Image> Image { get; set; }
}
public class Image
{
public int ImageID { get; set; }
[Required]
public int JobDescriptionID { get; set; }
[ForeignKey("JobDescriptionID")]
public virtual JobDescription JobDescription { get; set; }
public virtual List<ImageSection> ImageSection { get; set; }
}
public class ImageSection
{
public int ImageSectionID { get; set; }
//
public int ImageID { get; set; }
[ForeignKey("ImageID")]
public virtual Image Image { get; set; }
public virtual DigitalSection DigitalSection { get; set; }
}
public class DigitalSection
{
public int DigitalSectionID { get; set; }
public int ImageSectionID { get; set; }
[ForeignKey("ImageSectionID")]
public virtual ImageSection ImageSection { get; set; }
public virtual VerifiedSection VerifiedSection { get; set; }
}
public class VerifiedSection
{
public int VerifiedSectionID { get; set; }
public string DigitizedText { get; set; }
public int DigitalSectionID { get; set; }
[ForeignKey("DigitalSectionID")]
public virtual DigitalSection DigitalSection { get; set; }
}
I am using CodeFirst approach and I have JobDscriptionID. Now i want to retireve all the DigitizedText from VerifiedSection Table. How to do it ?

Answer 1

Try this :
var result = contetx.VerifiedSection
.Where(V => V.DigitalSection.ImageSection.Image.JobDescription.JobDescriptionID == 1)
.Select(V => V.DigitizedText);
Alternately you could also use Join
var result = context.VerifiedSection.Join(context.DigitalSection.Join(
(context.ImageSection.Join
(context.Image.Join
(context.JobDescription.Where(J=> .JobDescriptionID == 1)), I=> I.JobDescriptionID, J => J.JobDescriptionID , (I,J) => I)
IS => IS.ImageID, I=> I.ImageID, (IS,I) => IS)
D => D.ImageSectionID, IS => IS.ImageSectionID , (D,IS) => D)
V => V.DigitalSectionID, D => D.DigitalSectionID, (V,D) => V.DigitizedText);
Good Luck !!

Answer 2

var query = (from image in Context.Image
Where image.JobDescriptionID == id
select image.ImageID).SingleOrDefault();
var query2 = (from select in Context.ImageSection
Where select.ImageID == query
select select.ImageSectionID).SingleOrDefault();
var query3 = (from digital in Context.DigitalSection
Where digital.ImageSectionID == query2
select digital.DigitalSectionID).SingleOrDefault();
var query4 = from text in Context.VerifiedSection
Where text.VerifiedSection == query3
select select.DigitizedText;
Kundan Singh Chouhan gave you a better answer, but perhaps you'd like to do it the "Queries" way.