How do I modify the data inside a MonoBehaviour?

[nsunh]

I want to change the data values in the blue part.
I've tried various methods, but haven't found a way to access that field.
Can you help me with this?

[nsunh]

I used GetChildrenList(), but it didn't work at all. Do I need to approach data of type Array differently?

[nesrak1]

Set just the first value:
AT2: baseField["tips"]["Array"][0].GetValue().Set(someValue)
AT3: baseField["tips.Array"][0].AsString = someValue

Iterate all values in the array:
AT2: foreach (var data in baseField["tips"]["Array"].GetChildrenList())
AT3: foreach (var data in baseField["tips.Array"])

[nsunh]

Thank you so much for your quick response.
However, I have encountered the following problem
I apologize for bothering you, but is there any way to resolve this?
I am using the latest version of AssetsTool.net.

[nesrak1]

You're trying to read/write a MonoBehaviour in AT2, so you need to do a little bit of extra code for it instead of just doing GetTypeInstance(...).GetBaseField(). Information about that is at https://github.com/nesrak1/AssetsTools.NET#reading-a-monobehaviour in the readme.

If you use AT3, this was simplified quite a bit.

[nsunh]

Thank you for your help. I'll fix it and share the results:)

[nsunh]

Thanks again for your help. I feel very fortunate to have gotten such an immediate response.
I can see how much you care about your project.
But because of my inexperience, I'm stuck again.

using AssetsTools.NET.Extra;
using AssetsTools.NET;
using AssetsTools;
using System.IO;

var am = new AssetsManager();
var inst = am.LoadAssetsFile("C:\Program Files (x86)\Steam\steamapps\common\Dinkum\Dinkum_Data\level0", true);
//call am, load file
am.LoadClassPackage("C:\Users\nsunh\source\repos\DinkumKR\DinkumKR\lib\classdata.tpk");
am.LoadClassDatabaseFromPackage(inst.file.typeTree.unityVersion);
//load classdata
var lScreenObjInf = inst.table.GetAssetInfo("LoadingScreenImageAndTips");
var lScreenObjBf = am.GetTypeInstance(inst, lScreenObjInf).GetBaseField();
var lScreenCompArr = lScreenObjBf.Get("m_Component").Get("Array");
//set Inf, Bf, Arr of GameObj
AssetFileInfoEx monoBehaviourInf = null;
AssetTypeValueField monoBehaviourBf = null;
//set inf, Bf of mono
for (var i = 0; i < lScreenCompArr.GetChildrenCount(); i++)
{
//get comp inf (but don't deserialize yet)
var childPtr = lScreenCompArr[i].Get("component");
var childExt = am.GetExtAsset(inst, childPtr, true);
var childInf = childExt.info;

//skip if not MonoBehaviour
if (childInf.curFileType != (uint)AssetClassID.MonoBehaviour)
    continue;

//check the MonoScript for its class name

//deserialize the MonoBehaviour asset
childExt = am.GetExtAsset(inst, lScreenCompArr[i], false);
var childBf = childExt.instance.GetBaseField();
var monoScriptPtr = childBf.Get("m_Script");

//get MonoScript from MonoBehaviour
var monoScriptExt = am.GetExtAsset(childExt.file, monoScriptPtr);
var monoScriptBf = monoScriptExt.instance.GetBaseField();

var className = monoScriptBf.Get("m_ClassName").GetValue().AsString();
if (className == "LoadingScreenImageAndTips")
{
    //we found the script, now we can edit it
    monoBehaviourInf = childInf;
    monoBehaviourBf = childBf;
    break;
}

}
if (monoBehaviourInf == null)
throw new Exception("couldn't find Script on this GameObj");

////load MonoBehaviour fields on top of regular fields
var managedFolder = Path.Combine(Path.GetDirectoryName(inst.path), "Managed");
monoBehaviourBf = MonoDeserializer.GetMonoBaseField(am, inst, monoBehaviourInf, managedFolder);

//change mono field
monoBehaviourBf["tips"]["Array"][0].GetValue().Set("Thank you!");

var newMonoBytes = monoBehaviourBf.WriteToByteArray();
var repl = new AssetsReplacerFromMemory(
0, monoBehaviourInf.index, (int)monoBehaviourInf.curFileType,
AssetHelper.GetScriptIndex(inst.file, monoBehaviourInf),
newMonoBytes
);

using (var stream = File.OpenWrite("resources-modified.assets"))
using (var writer = new AssetsFileWriter(stream))
{
inst.file.Write(writer, 0, new List() { repl }, 0);
}

am.UnloadAllAssetsFiles();

Here's the full code I used.
When I built this code, I encountered the following problem.

So, I made the following changes to my code and built it.

I don't know if this is the right way to do it, but I ran into the following problem before I could confirm that it worked.

//The structure of the game object.

//first try

//second

[nesrak1]

I forgot that the game has to use IL2CPP (it's a switch game), but only mono games are supported in AT2. AT3 supports IL2CPP with CPP2IL. You can get AT3 by building the upd21-with-inst branch or by installing the preview package on nuget. The documentation moved to the wiki for AT3: https://github.com/nesrak1/AssetsTools.NET/wiki/Getting-Started:-MonoBehaviour-reading

By the way, when you use AT3 you no longer need to call MonoDeserializer.GetMonoBaseField and can use the regular manager.GetBaseField.

[nsunh]

Thank you for your kind response! I'll give AT3 a try :)

[nsunh]

Thanks to you, we've solved it, and I'm so happy.
Finally, I have one question.
I used PathID to get the basefield.

However, when the version is updated, the pathID will also change, so I'm wondering if it's possible to get the basdfield by name like in AT2.
If not, should I write something like this?

foreach (var goInfo in afile.GetAssetsOfType(AssetClassID.MonoBehaviour))
{
var goBase = manager.GetBaseField(afileInst, goInfo);
if (goBase["m_Name"].AsString == "monoName")
{
...
}
}

[nsunh]

The mono doesn't have a name value, so I worked around it this way. I don't know if this is correct, but it works. Thanks for the help in the meantime :)