Creating multiple Page search/filtering system in best possible way

osyris zosar

5y700Learn iOS Programming

I know how to create single search on products

But how do I filter products base on multiple Fields

for example search on Title, price, brand and discription at the same time

What would be to most professional way to achive this

Single filter:

public async Task Index(string Title, string price, string discription , string brand)
{
var products = from m in _context.Product
select m;
if (!string.IsNullOrEmpty(Title))
{
products = _context.Product.Where(x => x.Title.ToLower().Contains(Title.ToLower()));
}
return View(await products.ToListAsync());
}

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Jignesh Kumar5y ago
Hi,

IActionResult : is for differnt purpose itself, It is interface for ActionResult base class and it is used in mvc action method for defferent type result return. Please refer this blog which will help you to understand better,

https://www.c-sharpcorner.com/blogs/iactionresult-vs-actionresult#:~:text=IActionResult%20is%20an%20interface%2C%20we,response%2C%20or%20error%20as%20well.

for IQuaryable, Please refer this one,
https://www.c-sharpcorner.com/UploadFile/a20beb/ienumerable-vs-iqueryable-in-linq/

Hope this will help you to get all.
+1
osyris zosar5y ago
So if I undertand you correclty:

it doesnt matter how many Iquaryable filters I use, Iquaryable always merges the filters together?
and what about this part:
public IQueryable GetProducts(ProductSearchModel searchModel)
the:
IQueryable
why is it placed there and not
async Task
as usually (where it allows multiple actions at the same time)
I have not seen that before, and can you place other codes there as well? if so what is the use for that?
+1
Sachin Singh5y ago
AsQueryable means do the filtering on the server side, that is you will get filtered data from sql server instead of all the data, it will reduce the space needed in memory.
Though it seems like filtering is happening in the memory but it is actually not the case rather you are getting filtered data.
+2
Jignesh Kumar5y ago
Hi,

Iquaryable is used when you want to query linq to SQL. Your all filter will execute at serverside so its good when you want to do serverside filter and get only required matching records which will improve performace and less load to in memoery.

IQuaryable supports lazzy loading as well so its very useful in this type of filter requirement.

Please refer this thred which will help you to undestand better,
https://www.c-sharpcorner.com/article/difference-between-iqueryable-and-ienumerable-while-working-in-linq/
+2
osyris zosar5y ago
Thank you very much it worked but i dont really understand how.
so please help me out understanding

The working code:
public IQueryable GetProducts(ProductSearchModel searchModel)
        {
            var result = _context.Product.AsQueryable();

            if (searchModel != null)
            {
                if (searchModel.Id.HasValue)
                    result = result.Where(x => x.Id == searchModel.Id);
                if (!string.IsNullOrEmpty(searchModel.Name))
                    result = result.Where(x => x.Title.Contains(searchModel.Name));
                if (searchModel.PriceFrom.HasValue)
                    result = result.Where(x => x.Price >= searchModel.PriceFrom);
                if (searchModel.PriceTo.HasValue)
                    result = result.Where(x => x.Price <= searchModel.PriceTo);
            }

            return result;
        }

        public async Task Index(ProductSearchModel searchModel, string Title, string PriceFrom, string PriceTo)
        {
            var DbProducts = from m in _context.Product
                           select m;

            if (!string.IsNullOrEmpty(Title))
                searchModel.Name = Title;
            if (!string.IsNullOrEmpty(PriceFrom))
            {
                bool priceF = int.TryParse(PriceFrom, out int s);
                if (priceF)
                    searchModel.PriceFrom = s;
            }
            if (!string.IsNullOrEmpty(PriceTo))
            {
                bool priceT = int.TryParse(PriceTo, out int x);
                if (priceT)
                    searchModel.PriceFrom = x;
            }


            return View(GetProducts(searchModel));

        }
It is this part that i dont understand:
public IQueryable GetProducts(ProductSearchModel searchModel)
    {
        var result = _context.Product.AsQueryable();

        if (searchModel != null)
        {
            if (searchModel.Id.HasValue)
                result = result.Where(x => x.Id == searchModel.Id);
            if (!string.IsNullOrEmpty(searchModel.Name))
                result = result.Where(x => x.Title.Contains(searchModel.Name));
            if (searchModel.PriceFrom.HasValue)
                result = result.Where(x => x.Price >= searchModel.PriceFrom);
            if (searchModel.PriceTo.HasValue)
                result = result.Where(x => x.Price <= searchModel.PriceTo);
        }

        return result;
    }
I am not familiar with this code:
public IQueryable
I am only used using:
public async Task
//OR
public IActionResult
1. What does the IQueryable actualy do and why is it used after the "Public" and not as a parameter?
2. and why does the "Var result" need to use ".AsQueryable()"
3. How does this part:
if (searchModel.Id.HasValue)
                    result = result.Where(x => x.Id == searchModel.Id);
                if (!string.IsNullOrEmpty(searchModel.Name))
                    result = result.Where(x => x.Title.Contains(searchModel.Name));
                if (searchModel.PriceFrom.HasValue)
                    result = result.Where(x => x.Price >= searchModel.PriceFrom);
                if (searchModel.PriceTo.HasValue)
                    result = result.Where(x => x.Price <= searchModel.PriceTo);
filters everything at the same time perfectly and prevents duplicates as well
its all pretty confusing to me
+1
Jignesh Kumar5y ago
Hi, Please refer this one.

It's good approach to solve your issue, Create one model with all four paremeter and pass then to method from where you can filter your data with your multiple field filter.
https://entityframework.net/knowledge-base/33153932/filter-search-using-multiple-fields---asp-net-mvc
+2