Version: 2021.1
LanguageEnglish
  • C#

QueryEngine<T0>.SetDefaultParamFilter

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Declaration

public void SetDefaultParamFilter(Func<TData,string,string,string,string,bool> handler);

Parameters

handler Callback used to handle the function filter. Takes an object of type TData, the filter identifier, the parameter, the operator, and the filter value, and returns a boolean indicating if the filter passed or not.

Description

Sets the default filter handler for function filters that were not registered.

using System.Collections.Generic;
using System.Linq;
using UnityEditor;
using UnityEditor.Search;
using UnityEngine;

static class Example_QueryEngine_SetDefaultParamFilter
{
    static List<MyObjectType> s_Data;

    [MenuItem("Examples/QueryEngine/SetDefaultParamFilter")]
    public static void RunExample()
    {
        // Set up the query engine
        var queryEngine = new QueryEngine<MyObjectType>();
        queryEngine.SetSearchDataCallback(myObj => new[] { myObj.id.ToString(), myObj.name });

        // Add a filter for MyObjectType.id that supports all operators
        queryEngine.AddFilter("id", myObj => myObj.id);

        // Register a default filter handler for any filter with parameters.
        queryEngine.SetDefaultParamFilter((myObj, filterId, paramValue, operatorToken, filterValue) =>
        {
            if (myObj.property.name != filterId)
                return false;

            if (myObj.property.type == PropertyType.Integer_Array)
            {
                if (!(myObj.property.value is int[] integerArray))
                    return false;
                if (!int.TryParse(paramValue, out var indexValue))
                    return false;
                if (!int.TryParse(filterValue, out var filterValueInt))
                    return false;
                if (indexValue < 0 || indexValue >= integerArray.Length)
                    return false;
                switch (operatorToken)
                {
                    case "=": return integerArray[indexValue] == filterValueInt;
                    case "!=": return integerArray[indexValue] != filterValueInt;
                    case "<": return integerArray[indexValue] < filterValueInt;
                    case ">": return integerArray[indexValue] > filterValueInt;
                    case "<=": return integerArray[indexValue] <= filterValueInt;
                    case ">=": return integerArray[indexValue] >= filterValueInt;
                    default: return false;
                }
            }

            return false;
        });

        s_Data = new List<MyObjectType>()
        {
            new MyObjectType { id = 0, property = new Property("values", PropertyType.Integer_Array, new int[] {0, 2, 42}) },
            new MyObjectType { id = 1, property = new Property("weights", PropertyType.Integer_Array, new int[] {1000, 250, 400}) }
        };

        // Find all items that have the property "values" higher than 10 at index 2
        var query = queryEngine.Parse("values(2)>10");
        var filteredData = query.Apply(s_Data).ToList();
        Debug.Assert(filteredData.Count == 1, $"There should be 1 item in the filtered list but found {filteredData.Count} items.");
        Debug.Assert(filteredData.Contains(s_Data[0]), "The first item should be in the filtered list since its property \"values\" has a value higher than 10 at index 2.");
    }

    enum PropertyType
    {
        Integer,
        String,
        Integer_Array
    }
    struct Property
    {
        public string name { get; }
        public PropertyType type { get; }
        public object value { get; set; }

        public Property(string name, PropertyType type, object value)
        {
            this.name = name;
            this.type = type;
            this.value = value;
        }
    }

    class MyObjectType
    {
        public int id { get; set; }
        public string name { get; set; } = string.Empty;
        public Vector2 position { get; set; } = Vector2.zero;
        public bool active { get; set; }
        public Property property { get; set; }

        public override string ToString()
        {
            return $"({id}, {name}, ({position.x}, {position.y}), {active})";
        }
    }
}