使用TDictionary.Add访问冲突

Question

任何人都知道我为何会通过以下获取访问权限：

  unit TestForm;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Generics.Collections, Vcl.Grids,
  Vcl.ValEdit;

type

  TClientThing = class
  private
    iCDic: TDictionary<string, string>;
  published
    property Dic: TDictionary<string, string> read iCDic write iCDic;

  end;

  TForm1 = class(TForm)
    vleHeader: TValueListEditor;
    procedure FormCreate(Sender: TObject);

  private
    { Private declarations }
    ClientThing: TClientThing;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
var
  vCustomParamKey: string;
  vCustomValueKey: string;
  J: integer;

begin

  with ClientThing do
  begin

    // Get the header params from the config and list edit...
    for J := 0 to vleHeader.RowCount - 1 do
    begin
      vCustomParamKey := vleHeader.Cells[0, J];
      vCustomValueKey := vleHeader.Cells[1, J];
      Dic.Add(vCustomParamKey, vCustomValueKey);

    end;
  end;
end;

end.

访问冲突位于Dic.Add行。例外是：

我整晚都在上班，所以可能错过了什么。 TValueListEditor内容是（代码编辑器视图）：

X-Application=g9V0rB9a3J5UF8
X-Authentication=kQNvuuimr0yMtEYZtXAZntTScPlvjecEAGtvbnNIU=
JSONRpc=2.0

Answer 1

表单永远不会为ClientThing分配值，因此它仍为nil。为其分配值，然后为iCDic分配值。当您使用调试器逐步执行代码时，您应该能够检测到此问题。