Version: 2021.3
LanguageEnglish
  • C#

QueryEngine<T0>.SetDefaultFilter

Suggest a change

Success!

Thank you for helping us improve the quality of Unity Documentation. Although we cannot accept all submissions, we do read each suggested change from our users and will make updates where applicable.

Close

Submission failed

For some reason your suggested change could not be submitted. Please <a>try again</a> in a few minutes. And thank you for taking the time to help us improve the quality of Unity Documentation.

Close

Cancel

Declaration

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

Parameters

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

Description

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

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

static class Example_QueryEngine_SetDefaultFilter
{
    static List<MyObjectType> s_Data;

    [MenuItem("Examples/QueryEngine/SetDefaultFilter")]
    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);

        // For all other filters, you can register a "default" filter handler that will be called when
        // an unknown filter token is encountered. It can also be useful for dynamic properties.
        queryEngine.SetDefaultFilter((myObj, filterId, operatorToken, filterValue) =>
        {
            if (myObj.property.name != filterId)
                return false;

            if (myObj.property.type == PropertyType.String)
            {
                if (!(myObj.property.value is string s))
                    return false;
                switch (operatorToken)
                {
                    case ":": return s.Contains(filterValue);
                    case "=": return s == filterValue;
                    default: return false;
                }
            }

            if (myObj.property.type == PropertyType.Integer)
            {
                if (!(myObj.property.value is int i))
                    return false;
                if (!int.TryParse(filterValue, out var filterValueInt))
                    return false;
                switch (operatorToken)
                {
                    case "=": return i == filterValueInt;
                    case "!=": return i != filterValueInt;
                    case "<": return i < filterValueInt;
                    case ">": return i > filterValueInt;
                    case "<=": return i <= filterValueInt;
                    case ">=": return i >= filterValueInt;
                    default: return false;
                }
            }

            return false;
        });

        s_Data = new List<MyObjectType>()
        {
            new MyObjectType { id = 0, property = new Property("size", PropertyType.Integer, 64) },
            new MyObjectType { id = 1, property = new Property("size", PropertyType.Integer, 128) },
            new MyObjectType { id = 2, property = new Property("tag", PropertyType.String, "item") },
            new MyObjectType { id = 3, property = new Property("tag", PropertyType.String, "car item") }
        };

        // Find all items that have the property "size" that is equal to 64
        var query = queryEngine.Parse("size=64");
        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 \"size\" has a value of 64.");

        // Find all items that have the property "tag" that contains "item"
        query = queryEngine.Parse("tag:item");
        filteredData = query.Apply(s_Data).ToList();
        Debug.Assert(filteredData.Count == 2, $"There should be 2 item in the filtered list but found {filteredData.Count} items.");
        Debug.Assert(filteredData.Contains(s_Data[2]), "The third item should be in the list as its property \"tag\" contains \"item\".");
        Debug.Assert(filteredData.Contains(s_Data[3]), "The fourth item should be in the list as its property \"tag\" contains \"item\".");
    }

    enum PropertyType
    {
        Integer,
        String
    }
    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})";
        }
    }
}

Copyright © 2023 Unity Technologies
优美缔软件(上海)有限公司 版权所有
"Unity"、Unity 徽标及其他 Unity 商标是 Unity Technologies 或其附属机构在美国及其他地区的商标或注册商标。其他名称或品牌是其各自所有者的商标。
公安部备案号:
31010902002961