Version: 2020.3
  • C#


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public static Unity.IO.LowLevel.Unsafe.ReadHandle Read(string filename, ReadCommand* readCmds, uint readCmdCount, string assetName, ulong typeID, Unity.IO.LowLevel.Unsafe.AssetLoadingSubsystem subsystem);


filename The filename to read from.
readCmds A pointer to an array of ReadCommand structs that specify offset, size, and destination buffer.
readCmdCount The number of read commands pointed to by readCmds.
assetName (Optional) The name of the object being read, for metrics purposes.
typeID (Optional) The TypeID of the object being read, for metrics purposes.
subsystem (Optional) The Subsystem tag for the read operation, for metrics purposes.


ReadHandle Used to monitor the progress and status of the read command.


Issues an asynchronous file read operation. Returns a ReadHandle.

You can set the assetName, typeId, and subsystem parameters to collect asset-specific metrics for this read operation. When you enable metrics collection with AsyncReadManagerMetrics.StartCollectingMetrics, Unity includes this information as part of the AsyncReadManagerMetrics, allowing you to analyze how different types of assets affect performance.

using System.IO;
using Unity.Collections;
using Unity.IO.LowLevel.Unsafe;
using Unity.Collections.LowLevel.Unsafe;
using UnityEngine;

class AsyncReadSample : MonoBehaviour { private ReadHandle readHandle; NativeArray<ReadCommand> cmds; string assetName = "myfile"; ulong typeID = 114; // from ClassIDReference AssetLoadingSubsystem subsystem = AssetLoadingSubsystem.Scripts;

public unsafe void Start() { string filePath = Path.Combine(Application.streamingAssetsPath, "myfile.bin"); cmds = new NativeArray<ReadCommand>(1, Allocator.Persistent); ReadCommand cmd; cmd.Offset = 0; cmd.Size = 1024; cmd.Buffer = (byte*)UnsafeUtility.Malloc(cmd.Size, 16, Allocator.Persistent); cmds[0] = cmd; readHandle = AsyncReadManager.Read(filePath, (ReadCommand*)cmds.GetUnsafePtr(), 1, assetName, typeID, subsystem); }

public unsafe void Update() { if (readHandle.IsValid() && readHandle.Status != ReadStatus.InProgress) { Debug.LogFormat("Read {0}", readHandle.Status == ReadStatus.Complete ? "Successful" : "Failed"); readHandle.Dispose(); UnsafeUtility.Free(cmds[0].Buffer, Allocator.Persistent); cmds.Dispose(); } } }