问题遇到的现象和发生背景
```c#
;//PresentationControls.CheckBoxProperties checkBoxProperties = new PresentationControls.CheckBoxProperties();
checkBoxProperties.ForeColor = System.Drawing.SystemColors.ControlText;
this.cmb_camList.CheckBoxProperties = checkBoxProperties;
this.cmb_camList.DisplayMemberSingleItem = "";
this.cmb_camList.FormattingEnabled = true;
this.cmb_camList.Name = "cmb_camList";
this.cmb_camList.TabIndex = 7;
```属性集合