Faceted search on multilist in sitecore 7 - sitecore

Question

I'm able to generate the facet and bind the result in Linkbutton within repeater control. Now I'm facing problem in generating the facet query with OR operator when the user selects more than 1 value of same facet type in Sitecore 7.
What can be done to solve it?
Thanks

Answer 1

Here's a blog post about solving this using PredicateBuilder with a specific code example:
http://www.nttdatasitecore.com/en/Blog/2013/November/Building-Facet-Queries-with-PredicateBuilder.aspx

Answer 2

To implement the Facet search in Sitecore use PredicateBuilder class to build the filter query and then add the filter query to the base query. Code is mentioned below:
List<PeopleFields> objPeoplefields = new List<PeopleFields>();
IQueryable<PeopleFields> Query = null;
var predicatePractice = Sitecore.ContentSearch.Utilities.PredicateBuilder.False<PeopleFields>();
var predicateOffice = Sitecore.ContentSearch.Utilities.PredicateBuilder.False<PeopleFields>();
using (var context = ContentSearchManager.GetIndex(SITECORE_WEB_INDEX).CreateSearchContext())
{
//Base query
Query = context.GetQueryable<PeopleFields>().Where(i => i.FirstName.StartsWith(txtFirstName.Text)).Where(i => i.LastName.StartsWith(txtLastName.Text));
foreach (string strselecteFacet in lstPracticefacetSelected)
{
//filter query
predicatePractice = predicatePractice.Or(x => x.Practice.Like(strselecteFacet));
}
foreach (string strselecteFacet in lstOfficefacetSelected)
{
//Filter query
predicateOffice = predicateOffice.Or(x => x.Office.Like(strselecteFacet));
}
//Joining the filter query alongwith base query
if (lstPracticefacetSelected.Count > 0 && lstOfficefacetSelected.Count > 0)
Query = Query.Filter(predicatePractice).Filter(predicateOffice);
else if (lstPracticefacetSelected.Count > 0 && lstOfficefacetSelected.Count == 0)
Query = Query.Filter(predicatePractice);
else if (lstPracticefacetSelected.Count == 0 && lstOfficefacetSelected.Count > 0)
Query = Query.Filter(predicateOffice);
objPeoplefields = Query.ToList();
}

Answer 3

As a quick way, if you're ok with having SitecoreUISearchResultItem as the query result type, you may be able to utilize the same method Sitecore 7 uses to parse queries entered in the content editor search:
Sitecore.Buckets.Util.UIFilterHelpers.ParseDatasourceString(string query)
If that's not up to what you're after, reading how it's implemented with a decompiler (ILSpy, DotPeek, Reflector, Resharper, etc) may help you in composing an expression manually based on dynamic criteria.