ソースコード

using System.Linq;
using UnityEditor;

public static class Example
{
    [MenuItem( "Tools/Snap All" )]
    private static void SnapAll()
    {
        var list = Selection.gameObjects
            .Select( c => c.GetComponent<UISprite>() )
            .Where( c => c != null )
            .ToArray()
        ;
        
        foreach ( var n in list )
        {
            n.MakePixelPerfect();
        }
    }
}

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