private Expression GenerateFilter <T>(ParameterExpression pe, JQGridSearch search)
{
//multiple search query
Expression Query = null;
if (search.groups.Count() > 0)
{
//multiple group query
foreach (JQGridSearch item in search.groups)
{
if (Query == null)
{
Query = GenerateFilter <T>(pe, item);
}
else
{
if (search.groupOp == "AND")
{
Query = Expression.AndAlso(Query, GenerateFilter <T>(pe, item));
}
else
{
Query = Expression.OrElse(Query, GenerateFilter <T>(pe, item));
}
}
}
}
else if (search.rules.Count() > 0)
{
foreach (JQGridSearchRule item in search.rules)
{
if (Query == null)
{
Query = FilterExpression <T>(pe, item);
}
else
{
if (search.groupOp == "AND")
{
Query = Expression.AndAlso(Query, FilterExpression <T>(pe, item));
}
else
{
Query = Expression.OrElse(Query, FilterExpression <T>(pe, item));
}
}
}
}
return(Query);
}
public JQGridResponse <T> Query <T>(Entities entity, HttpRequestMessage Request)
{
dynamic instance = Activator.CreateInstance(typeof(T));
int PageSize = 0;
int Page = 0;
string SortColumn = "";
string SortOrder = "";
bool search = false;
string SingleSearch_Field = "";
string SingleSearch_Value = "";
string SingleSearch_Oper = "";
MethodCallExpression WhereClause = null;
var model = entity.Set(typeof(T)).OfType <T>();
if (Request.GetQueryNameValuePairs().Where(x => x.Key == "rows").First().Value != "")
{
PageSize = int.Parse(Request.GetQueryNameValuePairs().Where(x => x.Key == "rows").First().Value);
}
if (Request.GetQueryNameValuePairs().Where(x => x.Key == "page").First().Value != "")
{
Page = int.Parse(Request.GetQueryNameValuePairs().Where(x => x.Key == "page").First().Value);
}
if (Request.GetQueryNameValuePairs().Where(x => x.Key == "sidx").First().Value != "")
{
SortColumn = Request.GetQueryNameValuePairs().Where(x => x.Key == "sidx").First().Value;
}
if (Request.GetQueryNameValuePairs().Where(x => x.Key == "sord").First().Value != "")
{
SortOrder = Request.GetQueryNameValuePairs().Where(x => x.Key == "sord").First().Value;
}
Type type = typeof(T);
ParameterExpression pe = Expression.Parameter(type, "p");
//search options
if (Request.GetQueryNameValuePairs().Where(x => x.Key == "_search").First().Value == "true")
{
search = true;
Expression Queryfilter = null;
if (Request.GetQueryNameValuePairs().Where(x => x.Key == "searchField").First().Value != "")
{
//single search
SingleSearch_Field = Request.GetQueryNameValuePairs().Where(x => x.Key == "searchField").First().Value;
SingleSearch_Value = Request.GetQueryNameValuePairs().Where(x => x.Key == "searchString").First().Value;
SingleSearch_Oper = Request.GetQueryNameValuePairs().Where(x => x.Key == "searchOper").First().Value;
Queryfilter = FilterExpression <T>(pe, SingleSearch_Oper, SingleSearch_Field, SingleSearch_Value);
}
else
{
//get Search options
string searchstring = Request.GetQueryNameValuePairs().Where(x => x.Key == "filters").First().Value;
JQGridSearch objJSON = new JQGridSearch();
JObject jobject = JObject.Parse(searchstring);
objJSON.groupOp = (string)jobject["groupOp"];
objJSON.rules = JsonConvert.DeserializeObject <List <JQGridSearchRule> >(jobject["rules"].ToString());
if (jobject["groups"] != null)
{
objJSON.groups = JsonConvert.DeserializeObject <List <JQGridSearch> >(jobject["groups"].ToString());
}
else
{
objJSON.groups = new List <JQGridSearch>();
}
//groups = (List<JQGridSearch>)jobject.Children()["groups"].Values().ToList();
Queryfilter = GenerateFilter <T>(pe, objJSON);
}
WhereClause = Expression.Call(
typeof(Queryable),
"Where",
new Type[] { model.ElementType },
model.Expression,
Expression.Lambda <Func <T, bool> >(Queryfilter, new ParameterExpression[] { pe }));
model = model.Provider.CreateQuery <T>(WhereClause);
}
JQGridResponse <T> response = new JQGridResponse <T>();
response.page = Page;
response.records = model.LongCount();
response.total = (response.records % PageSize) == 0 ? response.records / PageSize : (response.records / PageSize) + 1;
if (PageSize != 0 && Page != 0 && SortColumn != "" && SortOrder != "")
{
if (search)
{
model = model.Provider.CreateQuery <T>(WhereClause);
response.rows = SortBy <T>(model, SortColumn, SortOrder).Skip((Page - 1) * PageSize).Take(PageSize);
}
else
{
response.rows = SortBy <T>(model, SortColumn, SortOrder).Skip((Page - 1) * PageSize).Take(PageSize);
}
}
else
{
if (search)
{
response.rows = model.Provider.CreateQuery <T>(WhereClause);
}
else
{
response.rows = model;
}
}
return(response);
}
