public static bool ValidateBlockchain()
{
using (var db = new BlockchainExampleEntities())
{
try
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
var Blockchain = db.Blockchain.AsNoTracking().OrderBy(b => b.Index).ToArray();
for (int i = 1; i < Blockchain.Count(); i++)
{
if (!(Blockchain[i].PrevHash == Blockchain[i - 1].Hash))
{
Console.WriteLine("Block no " + i + " is invalid");
return(false);
}
}
stopwatch.Stop();
Console.WriteLine("Blockchain is valid, checked in " + stopwatch.ElapsedMilliseconds + "ms");
}
catch (Exception)
{
return(false);
}
Console.ReadKey();
Environment.Exit(0);
return(true);
}
}
public int?AddBlock()
{
using (var db = new BlockchainExampleEntities())
{
using (
var dbTran = db.Database.BeginTransaction(IsolationLevel.Serializable))
{
try
{
if (ValidateBlock())
{
db.Blockchain.Add(this);
db.SaveChanges();
dbTran.Commit();
return(this.Index);
}
dbTran.Rollback();
return(null);
}
catch (Exception)
{
dbTran.Rollback();
return(null);
}
}
}
}
public Blockchain GetLastBlock()
{
using (var db = new BlockchainExampleEntities())
{
try
{
return(db.Blockchain.OrderByDescending(b => b.Index).First());
}
catch (Exception)
{
return(new Blockchain(0, string.Empty, string.Empty, string.Empty, 0));
}
}
}
public Data GetDataByID()
{
using (var db = new BlockchainExampleEntities())
{
try
{
return(db.Data.FirstOrDefault(u => u.ID == this.ID));
}
catch (Exception)
{
return(null);
}
}
}
public int?SaveDataInDatabase()
{
using (var db = new BlockchainExampleEntities())
{
try
{
db.Data.Add(this);
db.SaveChanges();
db.Dispose();
return(this.ID);
}
catch (Exception)
{
return(null);
}
}
}
public bool RemoveData()
{
BlockchainExampleEntities db = new BlockchainExampleEntities();
try
{
var DataToRemove = db.Data.FirstOrDefault(u => u.ID == this.ID);
if (DataToRemove == null)
{
throw new Exception();
}
db.Data.Remove(DataToRemove);
db.SaveChanges();
db.Dispose();
}
catch (Exception)
{
return(false);
}
return(true);
}
