how to generate where condition without multiple if condition using linq query

Question

I have 3 search textbox values. i need to check string.isnullorEmpty for each variable and have to compare with the linq query.

My Text Values:

1. Manufacturer

2. Project Code

3. PartNo

Conditions:

1. if i search any one of the above i should get the result

2. If i enter 3 box values i should get the result

3. If i enter any 2 then i should get result.

My code as follows

if (!string.IsNullOrEmpty(manufacturer))
        {
            var filteredResult = _entity.MaterialMasters.Where(x => x.Manufacturer == manufacturer);
        }
if (!string.IsNullOrEmpty(projectcode))
        {
            var filteredResult = _entity.MaterialMasters.Where(x => x.ProjectCode== projectcode);
        }
if (!string.IsNullOrEmpty(part))
        {
            var filteredResult = _entity.MaterialMasters.Where(x => x.Part== part);
        }

To avoid multiple conditions how to make dynamic where clause for this? Please find out the solution for this..

Answer 1

He wants to get rid of the if statements and write this all as a linq query. I think you want something like this

.Where(
s =>
(string.IsNullOrEmpty(manufacturer) | (s.Manufacturer == manufacturer)) &&
(string.IsNullOrEmpty(projectcode) | (s.ProjectCode == projectcode)) &&
(string.IsNullOrEmpty(part) | (s.Part== part))
).ToList();

Answer 2

You can just tag on multiple Where clauses

var filteredResult = _entity.MaterialMasters;
if (!string.IsNullOrEmpty(manufacturer))

    filteredResult = filteredResult.Where(x => x.Manufacturer == manufacturer);
}
if (!string.IsNullOrEmpty(projectcode))

    filteredResult = filteredResult.Where(x => x.ProjectCode == projectcode);
}
if (!string.IsNullOrEmpty(part))

    filteredResult = filteredResult.Where(x => x.Part == part);
}

They will work cumulatively, meaning that you can supply 1, 2 or 3 of the parameters and you'll get the appropriate results.

Answer 3

var filteredResult =
               _entity.Where(
                ent =>
                (!string.IsNullOrEmpty(manufacturer) && ent.Manufacturer == manufacturer)
                || (!string.IsNullOrEmpty(projectcode) && ent.ProjectCode == projectcode)
                || (!string.IsNullOrEmpty(part) && ent.Part == part));

This will get you any result for manufacturer, projectCode and part in one place.