关于 c#:Access Violation Exception 在访问 Object 的字段期间

Access Violation Exception during access of field of Object

在我的 .Net Core 2.0、ASP.Net react 项目中使用 Linq 时，我遇到了一个非常奇怪的行为：

当访问在 Linq "Select" 选择器中实例化的对象的字段时，它会抛出 "Access Violation Exception"

重现步骤(希望如此)：

视觉工作室 2017、15.7.4
创建新的 ASP.Net Core 2.0 项目
选择"反应"模板

改变 SampleDataController.cs 如下：

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[HttpGet("[action]")]

public string Objects()
{
var rng = new Random();
var ret = Enumerable.Range(1, 5).Select(index =>
new TableDef("User")
.AddField(new StringField("ID", Guid.NewGuid().ToString()))
.AddField(new StringField("Name","User" + index.ToString()))
);

return"[" +
ret.Select(x => x.ToJSONString()).Aggregate((current, next) => current +"," + next) +
"]";
}

具有以下类：

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public class TableDef
{
public string ID { get; private set; } = Guid.NewGuid().ToString();
public string LockedBy { get; private set; } ="";
public string Name { get; private set; }
public FieldDef[] Fields { get; private set; }

public TableDef(string name)
{
Name = name;
Fields = new FieldDef[0];
}

public TableDef AddField(FieldDef field)
{
field.Parent = this;
var flds = this.Fields;
Array.Resize(ref flds, flds.Length + 1);
flds[flds.Length - 1] = field;
this.Fields = flds;
return this;
}

public string ToJSONString()
{
return @" {""TableDef"": {""
""DefID"":""" + ID + @""",
""DefName"":""" + Name + @""",
""DefLockedBy"":""" + LockedBy + @"""}," +
Fields
.Select(x => ('"' + x.Name + @""" :""" + x.Value + '"'))
.Aggregate((current, next) => current +"," + next) +
"}";
}
}

public abstract class FieldDef
{
public string ID { get; protected set; } = Guid.NewGuid().ToString();
public string Name { get; protected set; }
public abstract string Value { get; set; }
public abstract string DefaultValue { get; set; }
public Boolean ReadOnly { get; protected set; } = false;
public Boolean IsDirty { get; set; } = false;
public TableDef Parent {
get { return Parent; }
set {
this.Parent = value;
ID = Parent.Name.Replace("","") +"_" + Name.Replace("","");
}
}
}

public class StringField : FieldDef
{
public override string Value {
get { return (IsDirty) ? Value : DefaultValue; }
set { this.Value = value; }
}
public override string DefaultValue { get; set; }

public StringField(string name, string defaultValue)
{
Name = name;
DefaultValue = defaultValue;
}

public StringField(string name, string defaultValue, Boolean readOnly)
{
Name = name;
DefaultValue = defaultValue;
ReadOnly = readOnly;
}
}

运行代码并单击"获取数据"链接时，应用程序完全死掉(至少在我的情况下)，在 Visual Studio 中甚至没有出现错误。调试刚刚结束，给我留下以下调试输出：

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The program '[20584] dotnet.exe: Program Trace' has exited with code 0 (0x0).
The program '[20584] dotnet.exe' has exited with code -1073741819 (0xc0000005) 'Access violation'.
The program '[20584] dotnet.exe: Managed (CoreCLR)' has exited with code -1 (0xffffffff).

当注释 public TableDef AddField(FieldDef field) 中的 field.Parent = this; 行时，代码运行顺利。可能值得注意的是，即使我在这一行设置了断点，程序也会死掉。由于这需要 2 或 3 秒，我设法从调试器的"自动"中间窗口中的字段中读取了一些变量，它们看起来非常好。一旦我尝试访问父字段，应用程序就会死掉。

我很确定这是我自己错误解释的一些继承的东西。

非常感谢任何帮助。谢谢。