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i got a question here,hope warmheat developer help.

this is the problem i meet:

i want to save a class instance's fields due to reflection,the code below:

private void SaveFields()
    fieldItemList.Clear();
    FieldInfo[] fields = GetType().GetFields(BindingFlags.Public | BindingFlags.Instance);
    for (int i = 0; i < fields.Length; i++)
        FieldInfo finfo = fields[i];
        FieldItem item = new FieldItem()
            ValName = finfo.Name,
            ValType = finfo.FieldType,
            ValValue = finfo.GetValue(this),
        fieldItemList.Add(item);
    string json = JsonModule.GetInstance().Serialize(fieldItemList);
    json = JsonModule.GetInstance().FormatJsonString(json);
    Debug.LogFormat("json = {0}", json);
    File.WriteAllText(@"E:\GithubRepo\ShaderSamples\ShaderSamples\fields.json", json);
it works,and the saved json like this:
    "ValName": "fVar",
    "ValType": "System.Single, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
    "ValValue": 2.0
    "ValName": "iVar",
    "ValType": "System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
    "ValValue": 1
    "ValName": "Gears",
    "ValType": "GearParam[], Assembly-CSharp, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null",
    "ValValue": [
            "Vec3": {
                "x": 1.0,
                "y": 2.0,
                "z": 3.0
            "Vec2": {
                "x": 1.0,
                "y": 2.0
            "FVar": 1.0,
            "IVar": 2
then when i use it for fill in new class instance's fields,code like this:
private void ApplyFields()
    string json = File.ReadAllText(@"E:\GithubRepo\ShaderSamples\ShaderSamples\fields.json");
    fieldItemList = JsonModule.GetInstance().Deserialize<List<FieldItem>>(json);
    Debug.LogFormat("fieldItemList = {0}", fieldItemList.Count);
    FieldInfo[] fields = GetType().GetFields(BindingFlags.Public | BindingFlags.Instance);
    for (int i = 0; i < fields.Length; i++)
        FieldInfo finfo = fields[i];
        for (int k = 0; k < fieldItemList.Count; k++)
            FieldItem item = fieldItemList[k];
            if (finfo.Name == item.ValName)
                finfo.SetValue(this, item.ValValue);
it cause error:
ArgumentException: Object of type 'System.Double' cannot be converted to type 'System.Single'.
System.RuntimeType.CheckValue (System.Object value, System.Reflection.Binder binder, System.Globalization.CultureInfo culture, System.Reflection.BindingFlags invokeAttr) (at :0)
System.Reflection.MonoField.SetValue (System.Object obj, System.Object val, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Globalization.CultureInfo culture) (at :0)
System.Reflection.FieldInfo.SetValue (System.Object obj, System.Object value) (at :0)
TestReflectEnum.ApplyFields () (at Assets/Scripts/TestReflectEnum.cs:82)
i think reflect fieldinfo.setvalue need the exactly object type to fill in,so i change code like this:
object obj = Convert.ChangeType(item.ValValue, item.ValType);
finfo.SetValue(this, obj);
but still cause error:
InvalidCastException: Object must implement IConvertible.
System.Convert.ChangeType (System.Object value, System.Type conversionType, System.IFormatProvider provider) (at :0)
System.Convert.ChangeType (System.Object value, System.Type conversionType) (at :0)
TestReflectEnum.ApplyFields () (at Assets/Scripts/TestReflectEnum.cs:82)
now the only way for me is write out all kind of object type condition,and change type object one by one,it's so troublesome way,i hope there is a common function for read object from txt/json,and could setvalue right - -
                Have you tried finfo.SetValue(this, Convert.ChangeType(value, propertyInfo.PropertyType), null);
– Vivek Nuna
                Dec 4, 2021 at 15:14
                thanks first,but i doesn't found the three parameters override function(setvalue),i am use .netframework 4.0 and 4.8,which .netframework or .netcore you use?
– yangyang2035
                Dec 5, 2021 at 3:22
        
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