Object reference not set

Hello Emmanuel,

As per the error Need to check object is null or not. as per the code it looks like need to check productModel.tblCategory is null. if it's null no need to execute that code or skip that part of code from execution.

Please check the below code:

public JsonResult SaveProduct(ProductViewModel productModel)
{
            ASPNETMASTERPOSTEntities db = new ASPNETMASTERPOSTEntities();
            var result = false;
            try
            {
                tblCategory category = new tblCategory();
                if(productModel.tblCategory != null){
                    if (productModel.tblCategory.CategoryId > 0)
                    {
                        category = db.tblCategories.Where(x => x.CategoryId ==                                          productModel.tblCategory.CategoryId).FirstOrDefault();
                    }
                    else
                    {
                        category.CategoryName = productModel.tblCategory.CategoryName;
                        if (productModel.tblCategory.CategoryId <= 0)
                            db.tblCategories.Add(category);
                        db.SaveChanges();
                        category.CategoryId = productModel.tblCategory.CategoryId;
                    }
                }
                tblProduct product = new tblProduct();
                if (productModel.ProductId > 0)
                {
                    product = db.tblProducts.Where(a => a.ProductId == productModel.ProductId).FirstOrDefault();
                }
                product.ProductName = productModel.ProductName;
                if(productModel.tblCategory != null)              
                    product.CategoryId = productModel.tblCategory.CategoryId;
                if (productModel.ProductId <= 0)
                {
                    db.tblProducts.Add(product);
                }

                db.SaveChanges();
                result = true;
            }
            catch (Exception ex)
            {
                throw ex;
            }
            return Json(result, JsonRequestBehavior.AllowGet);
}

Thanks

Vishal Joshi