private IEnumerable <DynamicSearchModel> MatchKeysWithProperties(PropertyInfo[] properties, IEnumerable <KeyValuePair <string, string> > items)
{
var theItems = new Dictionary <PropertyInfo, DynamicSearchModel>();
var quickProperties = properties.Select(x => new { Name = x.Name.ToLower(), Property = x });
foreach (var prop in items)
{
var matchingProp = quickProperties.SingleOrDefault(x => x.Name == prop.Key);
if (matchingProp == null)
{
throw new Exception("Unable to find a property that matches the property name.");
}
var result = theItems.TryGetValue(matchingProp.Property, out var value);
if (result)
{
value.Values.Add(prop.Value);
}
else
{
theItems.Add(matchingProp.Property, value = new DynamicSearchModel {
objectProperty = matchingProp.Property, Values = { prop.Value }
});
}
}
return(theItems.Select(x => x.Value).ToList());
}
public static IQueryable <T> StringSearch(IQueryable <T> query, DynamicSearchModel model)
{
ParameterExpression e = Expression.Parameter(typeof(T), model.objectProperty.Name);
MemberExpression m = Expression.MakeMemberAccess(e, model.objectProperty);
Expression buildingExpression = m;
if (model.objectProperty.PropertyType == typeof(string))
{
Expression callExpr = Expression.Call(buildingExpression, typeof(object).GetMethod("ToString", new Type[] { }));
Expression callExpr1 = Expression.Call(callExpr, typeof(string).GetMethod("ToLower", new Type[] { }));
buildingExpression = Expression.Call(callExpr1, typeof(string).GetMethod("Trim", new Type[] { }));
}
var Constants = new List <Expression>();
foreach (var prop in model.Values)
{
Expression expression = Expression.Constant(prop, prop.GetType());
expression = Expression.Convert(expression, model.objectProperty.PropertyType);
Constants.Add(Expression.Call(buildingExpression, model.objectProperty.PropertyType.GetMethod("Equals", new Type[] { model.objectProperty.PropertyType }), expression));
}
Expression chainedOrExp = null;
foreach (var binExp in Constants)
{
if (chainedOrExp == null)
{
chainedOrExp = binExp;
continue;
}
else
{
chainedOrExp = Expression.OrElse(chainedOrExp, binExp);
continue;
}
}
if (chainedOrExp == null)
{
chainedOrExp = Expression.Constant(true);
}
Expression <Func <T, bool> > lambda = Expression.Lambda <Func <T, bool> >(chainedOrExp, e);
return(query.Where(lambda));
}