How to update List View Model in Asp.net MVC - asp.net-mvc

Question

Hi I am facing issue in update records in MVC. I have created one list view model and in that i want to update some of the records but i am getting error. Please help me.
Here is my code:
public async Task<bool> AddPurchase(PurchaseOrderViewModel objModel, List<TableViewModel> tableListDto)
{
using (var txn = context.Database.BeginTransaction())
{
bool success = true;
try
{
PurchaseOrder purchase1 = new PurchaseOrder();
purchase1.LoginID = objModel.LoginID;
purchase1.SupplierID = objModel.SupplierID;
purchase1.SupplierName = objModel.SupplierName;
purchase1.LocationID = objModel.LocationID;
purchase1.Notes = objModel.Notes;
purchase1.Currency = objModel.Currency;
purchase1.TotalQuantity = objModel.TotalQuantity;
purchase1.TotalAmount = objModel.TotalAmount;
purchase1.TotalVolume = objModel.TotalVolume;
purchase1.TotalWeight = objModel.TotalWeight;
purchase1.TotalLandedCost = Convert.ToDecimal(objModel.TotalCost);
purchase1.TotalOtherCost = objModel.TotalOtherCost;
purchase1.Date_Of_Purchase = objModel.Date_Of_Purchase;
purchase1.Due_Date = objModel.Due_Date;
purchase1.Date_Arrived = objModel.Date_Arrived;
purchase1.Date_Departed = objModel.Date_Departed;
purchase1.CreatedBy = objModel.LoginID;
purchase1.CreatedOn = objModel.CreatedOn;
purchase1.UpdatedBy = objModel.LoginID;
purchase1.UpdatedOn = objModel.UpdatedOn;
purchase1.Status = StatusConstant.Active;
context.PurchaseOrders.Add(purchase1);
await context.SaveChangesAsync();
success = true;
int latest = purchase1.PurchaseID;
PO_Landed_Cost cost = new PO_Landed_Cost();
cost.LoginID = objModel.LoginID;
cost.PurchaseID = latest;
cost.Packaging_Costs = objModel.Packaging_Cost;
cost.Packaging_Costs_Date_Paid = objModel.Packaging_Costs_Date_Paid;
cost.Inspection_Costs = objModel.Inspection_Cost;
cost.Inspection_Costs_Date_Paid = objModel.Inspection_Costs_Date_Paid;
cost.Freight_And_Duty_Tax = objModel.Freight_Cost;
cost.Freight_And_Duty_Tax_Date_Paid = objModel.Freight_And_Duty_Tax_Date_Paid;
cost.Other_Costs = objModel.Other_Cost;
cost.Total_Landed_Cost = objModel.TotalOtherCost;
context.PO_Landed_Costs.Add(cost);
context.SaveChanges();
OrderDetail order = new OrderDetail();
PO_Landed_Cost_Spread spread1 = new PO_Landed_Cost_Spread();
List<DataDisplayViewModel> data = new List<DataDisplayViewModel>();
if (tableListDto != null)
{
foreach (var item in tableListDto)
{
//First we take all the basic things
var a = Convert.ToDecimal(item.Qty); //Quantity
var b = Convert.ToDecimal(purchase1.TotalQuantity); //Total Quantity
var e = Convert.ToDecimal(objModel.TotalOtherCost); //TotalOtherCost
var g = Convert.ToDecimal(item.Price); //Price
var j = Convert.ToDecimal(item.Volume); //Volume
var l = Convert.ToDecimal(item.Weight); //Weight
var c = Math.Round(Convert.ToDecimal((a / b) * 100), 2); //Total Percent(Quantity)
var f = Math.Round(Convert.ToDecimal(((c * e) / a) / 100), 2); // Quantity Unit Price(Indirect Cost)
var h = Math.Round(Convert.ToDecimal(f + g), 2); //Landed Cost Unit Price (Quantity)
var i = Math.Round(Convert.ToDecimal(h * a), 2); //New Total (Quantity)
var k = Math.Round(Convert.ToDecimal(a * j), 2); //Total Volume
var m = Math.Round(Convert.ToDecimal(a * l), 2); //Total Weight
DataDisplayViewModel datalist = new DataDisplayViewModel();
datalist.LoginID = objModel.LoginID;
datalist.PurchaseID = latest;
datalist.Stock_ID = item.Pid;
datalist.Stock_Name = item.ProductName;
datalist.Quantity = Convert.ToInt32(item.Qty);
datalist.Price = Convert.ToDecimal(item.Price);
datalist.Amount = Convert.ToDecimal(item.Amount);
datalist.Volume = Convert.ToInt32(item.Volume);
datalist.Total_Volume = Convert.ToInt32(k);
datalist.Weight = Convert.ToInt32(item.Weight);
datalist.Total_Weight = Convert.ToInt32(m);
datalist.Total_Percent = Convert.ToString(c);
datalist.Indirect_Cost_UnitPrice = Convert.ToString(f);
datalist.Landed_Cost_UnitPrice = Convert.ToString(h);
datalist.New_Amount = i;
data.Add(datalist);
}
var totalweight = data.Where(x => x.PurchaseID == latest).Select(x => x.Total_Weight).Sum();
var totalvolume = data.Where(x => x.PurchaseID == latest).Select(x => x.Total_Volume).Sum();
foreach (var item in tableListDto)
{
var z = Convert.ToInt32(item.Price);
var a = Convert.ToInt32(item.Qty); //Qty
var l = Convert.ToDecimal(item.Weight); //Weight
var j = Convert.ToDecimal(item.Volume); //Volume
var d = Math.Round(Convert.ToDecimal(((a * l) / totalweight) * 100), 2); //Total Percent Of Weight
var e = Convert.ToInt32(objModel.TotalOtherCost); //Total Other Cost
var f = Math.Round(Convert.ToDecimal(((d * e) / a) / 100), 2);
var h = Convert.ToDecimal(a + f); // Landed Cost Unit Price Of Weight
var i = Convert.ToString(h * a); // New Total Of Weight
var m = (a * j / totalvolume) * 100; //Total Percent Of Volume
var o = Math.Round(Convert.ToDecimal(((m * e) / a) / 100), 2); //Unit Price Of Volume
var q = Math.Round(Convert.ToDecimal(z + o), 2); // Landed Cost Unit Price Of Volume
var r = Convert.ToInt32(q * a); //New Total Of Volume
data.Where(x => x.PurchaseID == latest).FirstOrDefault();
data.Where(x => x.PurchaseID == latest).FirstOrDefault().Indirect_Cost_WeightUnitPrice = Convert.ToString(f);
data.Where(x => x.PurchaseID == latest).FirstOrDefault().Landed_Cost_WeightUnitPrice = Convert.ToString(h);
data.Where(x => x.PurchaseID == latest).FirstOrDefault().New_WeightAmount = Convert.ToDecimal(i);
data.Where(x => x.PurchaseID == latest).FirstOrDefault().Total_Percent_Volume = Convert.ToString(m);
data.Where(x => x.PurchaseID == latest).FirstOrDefault().Indirect_Cost_VolumeUnitPrice = Convert.ToString(o);
data.Where(x => x.PurchaseID == latest).FirstOrDefault().Landed_Cost_VolumeUnitPrice = Convert.ToString(q);
data.Where(x => x.PurchaseID == latest).FirstOrDefault().New_VolumeAmount = Convert.ToDecimal(r);
context.Entry(data).State = EntityState.Added;
context.SaveChanges();
}
foreach (var item in data)
{
order.LoginID = objModel.LoginID;
order.PurchaseID = item.PurchaseID;
order.Stock_ID = item.Stock_ID;
order.Quantity = item.Quantity;
order.Price = item.Price;
order.Amount = item.Amount;
order.CreatedBy = objModel.LoginID;
order.CreatedOn = objModel.CreatedOn;
order.UpdatedBy = objModel.LoginID;
order.UpdatedOn = objModel.UpdatedOn;
order.Status = StatusConstant.Active;
order.Stock_Name = item.Stock_Name;
order.Volume = item.Volume;
order.Total_Volume = item.Total_Volume;
order.Weight = item.Weight;
order.Total_Weight = item.Total_Weight;
context.OrderDetails.Add(order);
context.SaveChanges();
spread1.PurchaseID = item.PurchaseID;
spread1.OrderID = order.OrderID;
spread1.LoginID = item.LoginID;
spread1.Total_Percent = item.Total_Percent;
spread1.Indirect_Cost_UnitPrice = item.Indirect_Cost_UnitPrice;
spread1.Landed_Cost_UnitPrice = item.Landed_Cost_UnitPrice;
spread1.New_Amount = item.New_Amount;
spread1.Total_Percent_Volume = item.Total_Percent_Volume;
spread1.Indirect_Cost_VolumeUnitPrice = item.Indirect_Cost_VolumeUnitPrice;
spread1.Landed_Cost_VolumeUnitPrice = item.Landed_Cost_VolumeUnitPrice;
spread1.New_VolumeAmount = item.New_VolumeAmount;
spread1.Total_Percent_Weight = item.Total_Percent_Weight;
spread1.Indirect_Cost_WeightUnitPrice = item.Indirect_Cost_WeightUnitPrice;
spread1.Landed_Cost_WeightUnitPrice = item.Landed_Cost_WeightUnitPrice;
spread1.New_WeightAmount = item.New_WeightAmount;
context.PO_Landed_Cost_Spreads.Add(spread1);
context.SaveChanges();
}
}
else
{
order.LoginID = objModel.LoginID;
order.PurchaseID = latest;
order.CreatedBy = objModel.LoginID;
order.CreatedOn = objModel.CreatedOn;
order.UpdatedBy = objModel.LoginID;
order.UpdatedOn = objModel.UpdatedOn;
order.Status = StatusConstant.Active;
context.OrderDetails.Add(order);
context.SaveChanges();
PO_Landed_Cost_Spread spread = new PO_Landed_Cost_Spread();
spread.LoginID = objModel.LoginID;
spread.PurchaseID = latest;
spread.OrderID = order.OrderID;
context.PO_Landed_Cost_Spreads.Add(spread);
context.SaveChanges();
}
txn.Commit();
}
catch (Exception ex)
{
txn.Dispose();
success = false;
}
return success;
};
}
In this code i want to update records when first i need to find some values and then i need to update in the list view model and then i need to update in the table. But i am unable to do that. Please help me in this.