Version: 2022.2
LanguageEnglish
  • C#

ParsedQuery<T0>.returnPayloadIfEmpty

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

public bool returnPayloadIfEmpty;

Description

Boolean. Indicates if the original payload should be returned when the query is empty.

If set to true, returns the original payload when the query is empty. If set to false, returns an empty array.

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

static class Example_ParsedQuery_returnPayloadIfEmpty
{
    static List<MyObjectType> s_Data;

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

        s_Data = new List<MyObjectType>()
        {
            new MyObjectType { id = 0, name = "Test 1", position = new Vector2(0, 0), active = false },
            new MyObjectType { id = 1, name = "Test 2", position = new Vector2(0, 1), active = true }
        };

        // When setting "returnPayloadIfEmpty" to true, empty queries
        // will return the same data set that was passed as input. Otherwise,
        // it will return an empty set.
        var query = queryEngine.ParseQuery("");
        var filteredData = query.Apply(s_Data).ToList();
        Debug.Assert(filteredData.Count == s_Data.Count, "Filtered data should have the same number of items as the input to the query.");
        for (var i = 0; i < filteredData.Count; ++i)
        {
            Debug.Assert(filteredData[i] == s_Data[i], $"Filtered data at index {i} should be the same as the input.");
        }
    }

    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 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