c# - How do I map to and from a complex type in EF4.3 code-first? -

i've got entity type this:

public class invoice{     public int id { get; set; }     public invoicenumbersequence sequence { get; set; }     public decimal amount { get; set; } } 

the invoicenumbersequence looks this:

public class invoicenumbersequence {      public string prefix { get; set; }     public int number { get; set; }      public string getsequence() {         return prefix + number;     } } 

my problem have existing database cannot change , i'm trying map tables/columns domain model. here's how table looks:

[systeminvoices] invoice_id int inv_total decimal invoice_seq varchar(255) 

i have dbcontext this:

public mydatabasecontext : dbcontext {     public dbset<invoice> invoices { get; set; }      protected override void onmodelcreating(dbmodelbuilder modelbuilder) {         modelbuilder.entity<predictedheat>().totable("systeminvoices");         modelbuilder.entity<invoice>().haskey(p => p.id);         modelbuilder.entity<invoice>().property(p => p.id).hascolumnname("invoice_id");         modelbuilder.entity<invoice>().property(p => p.amount).hascolumnname("inv_total");                 //need here map invoice sequence database table     } } 

i need map invoicenumbersequence both directions... 1) database field invoicenumbersequence class, , 2) invoicenumbersequence.getsequence() method database field.

how can this?

so instead of getsequence use property:

public class invoicenumbersequence {      public string prefix { get; set; }     public int number { get; set; }      public string sequence {         { retrun prefix + number; }         set { // add parsing logic }     } } 

and in mapping add:

modelbuilder.complextype<invoicenumbersequence>()             .property(p => p.sequence)             .hascolumnname("invoice_seq"); modelbuilder.complextype<invoicenumbersequence>()             .ignore(p => p.prefix); modelbuilder.complextype<invoicenumbersequence>()             .ignore(p => p.number);