MOSS字段编辑权限控制方案（3）-重写表单字段呈现逻辑

MOSS字段编辑权限控制方案（3）-重写表单字段呈现逻辑 重写表单字段呈现逻辑，添加编辑权限控制----这是这个方案实现的核心了。

wss有一套模板的机制，系统的一些控件，包括一些webpart，如果UI比较复杂，都会采用模板来实现，详细请参考：
WSS3.0开发--页面定制（1）--修改列表的表单页面

列表的表单页面，包括查看dispform.aspx,editform.aspx,newform.aspx都采用了一个模板:ListForm,
这个模板嵌入了一个控件--Microsoft.SharePoint.WebControls.ListFieldIterator,这个控件枚举列表的所有字段，生成编辑页面。
那么我们的工作核心就是重写这个ListFieldIterator控件。

通过Reflector查看ListFieldIterator的代码，幸运的是，它不是internal的，那么我们可以继承这个控件实现新的逻辑。不过不幸得是，
ListFieldIterator内部引用了TemplateContainer控件，这个控件的某些重要属性是internal的，我们的代码没法直接设置，
不过我们还有一招：采用反射。

下面是ListFieldIterator原始的CreateControl方法代码：


[SharePointPermission(SecurityAction.Demand, ObjectModel=true)]


protected override void CreateChildControls()






{


this.Controls.Clear();


if (this.ControlTemplate == null)






{


throw new ArgumentException("Could not find ListFieldIterator control template.");


}


for (int i = 0; i < base.Fields.Count; i++)






{


SPField field = base.Fields[i];


if (!this.IsFieldExcluded(field))






{


TemplateContainer child = new TemplateContainer();


this.Controls.Add(child);


child.ControlMode = base.ControlMode;


child.FieldName = field.InternalName;


this.ControlTemplate.InstantiateIn(child);


}


}


}

下面是重写后的ListFieldIterator:




EditControlListFieldIterator


public class EditControlListFieldIterator : Microsoft.SharePoint.WebControls.ListFieldIterator






{




protected override void CreateChildControls()






{


//只处理编辑模式


if (this.ControlMode != SPControlMode.Edit)






{


base.CreateChildControls();


return;


}




SPUser currentUser = SPContext.Current.Web.CurrentUser ;




//站点管理员可以编辑所有字段


if (currentUser.IsSiteAdmin)






{


base.CreateChildControls();


return;


}




//获取权限配置信息


ListFieldEditSetting listSetting = ListFieldEditSetting.GetListSetting( this.ListId ) ;


if( listSetting == null || listSetting.Count == 0 )






{


base.CreateChildControls();


return ;


}




//base.CreateChildControls();


this.Controls.Clear();


if (this.ControlTemplate == null)






{


throw new ArgumentException("Could not find ListFieldIterator control template.");


}




SPFieldUserValue authorFieldValue = new SPFieldUserValue ( SPContext.Current.Web , ""+ this.ListItem["Author"] ) ;


SPUser author = authorFieldValue.User;




Type t = typeof(TemplateContainer);




//反射获取TemplateContainer的ControlMode属性


PropertyInfo ControlModeProp = t.GetProperty("ControlMode", BindingFlags.Instance | BindingFlags.NonPublic);


PropertyInfo FieldNameProp = t.GetProperty("FieldName", BindingFlags.Instance | BindingFlags.NonPublic);




for (int i = 0; i < base.Fields.Count; i++)






{


SPField field = base.Fields[i];




if (!this.IsFieldExcluded(field))






{


TemplateContainer child = new TemplateContainer();




this.Controls.Add(child);




FieldEditSetting set = listSetting.GetByFieldName(field.InternalName);




if (set != null && !set.CanEdit(currentUser, author))






{


//child.ControlMode = base.ControlMode;


//child.FieldName = field.InternalName;


//ControlModeProp.SetValue(child, this.ControlMode,null);


ControlModeProp.SetValue(child, SPControlMode.Display, null);


}




FieldNameProp.SetValue(child, field.InternalName, null);




this.ControlTemplate.InstantiateIn(child);




}


}




}






}对比以上两个类的CreateControl方法，相信大家应该了解这个解决方案的核心了。

然后，编写新的模板文件：




CodeArt_Templates.ascx




<%

@ Control Language="C#" AutoEventWireup="false" %>




<%

@Assembly Name="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>




<%

@Register TagPrefix="SharePoint" Assembly="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" namespace="Microsoft.SharePoint.WebControls"%>




<%

@Register TagPrefix="SPHttpUtility" Assembly="Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" namespace="Microsoft.SharePoint.Utilities"%>




<%

@ Register TagPrefix="wssuc" TagName="ToolBar" src="~/_controltemplates/ToolBar.ascx" %>




<%

@ Register TagPrefix="wssuc" TagName="ToolBarButton" src="~/_controltemplates/ToolBarButton.ascx" %>




<%

@ Register Assembly="CodeArt.SharePoint, Version=1.0.0.0, Culture=neutral, PublicKeyToken=2c606279787b575f" Namespace="CodeArt.SharePoint.WebPart" TagPrefix="codeArt" %>


<SharePoint:RenderingTemplate ID="ListForm" runat="server">


<Template>


<SPAN id='part1'>




<SharePoint:InformationBar runat="server"/>


<wssuc:ToolBar CssClass="ms-formtoolbar" id="toolBarTbltop" RightButtonSeparator=" " runat="server">


<Template_RightButtons>


<SharePoint:NextPageButton runat="server"/>


<SharePoint:SaveButton runat="server"/>


<SharePoint:GoBackButton runat="server"/>


</Template_RightButtons>


</wssuc:ToolBar>


<SharePoint:FormToolBar runat="server"/>


<TABLE class="ms-formtable" style="margin-top: 8px;" border=0 cellpadding=0 cellspacing=0 width=100%>


<SharePoint:ChangeContentType runat="server"/>


<SharePoint:FolderFormFields runat="server"/>




<codeArt:EditControlListFieldIterator runat="server"/>




<SharePoint:ApprovalStatus runat="server"/>


<SharePoint:FormComponent TemplateName="AttachmentRows" runat="server"/>


</TABLE>


<table cellpadding=0 cellspacing=0 width=100%><tr><td class="ms-formline"><IMG SRC="/_layouts/images/blank.gif" width=1 height=1 alt=""></td></tr></table>


<TABLE cellpadding=0 cellspacing=0 width=100% style="padding-top: 7px"><tr><td width=100%>


<SharePoint:ItemHiddenVersion runat="server"/>


<SharePoint:ParentInformationField runat="server"/>


<SharePoint:InitContentType runat="server"/>


<wssuc:ToolBar CssClass="ms-formtoolbar" id="toolBarTbl" RightButtonSeparator=" " runat="server">


<Template_Buttons>


<SharePoint:CreatedModifiedInfo runat="server"/>


</Template_Buttons>


<Template_RightButtons>


<SharePoint:SaveButton runat="server"/>


<SharePoint:GoBackButton runat="server"/>


</Template_RightButtons>


</wssuc:ToolBar>


</td></tr></TABLE>


</SPAN>




<SharePoint:AttachmentUpload runat="server"/>


<hr/>


</Template>


</SharePoint:RenderingTemplate>








<SharePoint:RenderingTemplate ID="FileFormFields" runat="server">


<Template>


<codeArt:EditControlListFieldIterator runat="server"/>


</Template>


</SharePoint:RenderingTemplate>
OK，我们已经给系统“所有”表单添加了了新的呈现逻辑--只有编辑权限的用户才能可以看到编辑控件。