请问在自定义weg控件中怎样引用调用它的网页的DataTable(已有数据),并且把字段内容显示出来？？？

[ahking]

请问在自定义weg控件中怎样引用调用它的网页的DataTable(已有数据),并且把字段内容显示出来？？？

[ahking]

我是在设计环境中设置该属性啊！！
[Bindable(true),
Category("data"),
DefaultValue("")]

[dragonsuc]

wrox书上的例题：
using System;
using System.Web;
using System.Web.UI;
using System.Collections;
using System.Web.UI.WebControls;

namespace WroxControls
{


// Naming container for template items

public class CollectionItem2 : WebControl, INamingContainer
{

object _dataitem;

public object DataItem
{
get{ return _dataitem; }
}

public CollectionItem2(object value)
{
_dataitem = value;
}
}

public class ICollectionLister2 : WebControl, INamingContainer
// Step 3
{

// The data source the control will enumerate

ICollection _datasource;

public ICollection DataSource
{
get { return _datasource; }
set { _datasource = value; }
}

// The template used for the header

ITemplate _headingStyle;

[TemplateContainer(typeof(ICollectionLister2))]
public ITemplate HeadingStyle
{
get{ return _headingStyle; }
set{ _headingStyle = value; }
}

// The template used for the item

ITemplate _itemStyle;

[TemplateContainer(typeof(CollectionItem2))]
public ITemplate ItemStyle
{
get{ return _itemStyle; }
set{ _itemStyle = value; }
}


// Create the child control hierarchy from viewstate only

protected override void CreateChildControls()
{
int iCount = 0;
int i;
CollectionItem2 item;

if ( _headingStyle != null )
_headingStyle.InstantiateIn( this );

iCount = (int) ViewState["count"];

for( i=0; i< iCount; i++ )
{
if ( _itemStyle != null )
{
item = new CollectionItem2( null );
_itemStyle.InstantiateIn( item );
Controls.Add( item );
}
}

}

// Create control hierarchy with the data source

protected override void OnDataBinding( EventArgs args )
{
base.OnDataBinding(args);

if ( _datasource == null )
throw new Exception("Control requires a data source");


ClearChildViewState();
Controls.Clear();

// Clear all controls and state

IEnumerator e;
int iCount = 0;

if ( _headingStyle != null )
_headingStyle.InstantiateIn( this );

e = _datasource.GetEnumerator();

CollectionItem2 item;

while( e.MoveNext() )
{
if ( _itemStyle != null )
{
item = new CollectionItem2( e.Current );
_itemStyle.InstantiateIn( item );
Controls.Add( item );
iCount++;

}
}

// Remember the number of controls, so we can recreate the
// same controls, without the data source.

ViewState["count"] = iCount;

// stop CreateChildControls() being called again
ChildControlsCreated = true;

// Ensure view state is being tracked
TrackViewState();
}
}
};

[webdiyer]

要在设计时绑定DataTable，你需要自己写个转换器，要不就算页面上有DataTable，它也不会给你列出来让你选择！

[ahking]

我不想列出来，只是想在设计时可以自己将页面上已有的DataTable传入控件，然后将数据写出来啊！！

[ahking]

怎样写个转换器呢？？

[ahking]

up

[ahking]

调用它的.cs文件中：
.....创建数据库连接
dzs_kenConn.Open();

SqlDataAdapter dzs_kenAdap = new SqlDataAdapter("select * from ken_plan ", dzs_kenConn);
SqlCommandBuilder ken_cb = new SqlCommandBuilder(dzs_kenAdap);
DataSet ds = new DataSet();
dzs_kenAdap.Fill(ds, "ken_plan");
ken_plan_tb = ds.Tables["ken_plan"];
web控件中：
htw.RenderBeginTag(HtmlTextWriterTag.Table);
for (int i=0; i < Rownum; i++)
{
htw.RenderBeginTag(HtmlTextWriterTag.Tr);
for (int j=0; j < Columnum; j++)
{
htw.RenderBeginTag(HtmlTextWriterTag.Td);
ken_plan_tb .Rows[i][j]//此处写表字段内容
htw.RenderEndTag();

}

htw.RenderEndTag();
}
htw.RenderEndTag();

[webdiyer]

给你的自定义控件加一个公共属性 public DataTable SourceTable{get{...}set{..}}
在引用时把引用页上的DataTable赋给这个属性就行了。

[webdiyer]

建议下载Wrox的那个控件代码自己看看，几句话说不清，而且我也好长时间没弄这个了！

[ken2003]

up

[ken2003]

up

[ken2003]

up

[ahking]

转换器

[ahking]

to:webdiyer(陕北吴旗娃)
这种情况下怎样写转换器呢？？

[ahking]

下载地址？哪个例子？

[webdiyer]

去www.wrox.com下载这本书的代码：
Professional ASP.NET Server Controls - Building Custom Controls with C#

[ahking]

哪章的呢？

[ahking]

看了两三天了，头晕眼花，始终不得要领，唉................

[ahking]

我不在设计环境中给表赋值，而在后台代码中：
<cc1:tbpage1 id="Tbpage11" runat="server" Columnum="3" Rownum="6" Dtbname=ken_plan_tb></cc1:tbpage1>，结果出错，怎么回事？
.cs中：
protected DataTable ken_plan_tb = new DataTable();
private void Page_Load(object sender, System.EventArgs e)
{


dzs_kenConn.Open();

SqlDataAdapter dzs_kenAdap = new SqlDataAdapter("select * from ken_plan ", dzs_kenConn);
SqlCommandBuilder ken_cb = new SqlCommandBuilder(dzs_kenAdap);


DataSet ds = new DataSet();
dzs_kenAdap.Fill(ds, "ken_plan");
ken_plan_tb = ds.Tables["ken_plan"];
}
web控件中：
private DataTable dtbname;

/*[Bindable(true),
Category("data"),
DefaultValue("")]*/
public DataTable Dtbname
{
get
{
return dtbname;
}

set
{
dtbname = value;
}
}
for (int i=0; i < Rownum; i++)
{
htw.RenderBeginTag(HtmlTextWriterTag.Tr);
for (int j=0; j < Columnum; j++)
{
htw.RenderBeginTag(HtmlTextWriterTag.Td);
htw.Write(dtbname.Rows[0][0].ToString());
htw.RenderEndTag();

}

htw.RenderEndTag();
}

[webdiyer]

你是要aspx页上写的，那不叫后台叫前台，而且写在aspx页上的ken_plan_tb不是DataTable而是字符串，应该这样用：
MyUserControl ctl=(MyUserControl)Page.LoadControl("myusercontrol.ascx");
DataTable table=new DataTable();
//填充DataTable
ctl.DtbName=table;
this.Controls.Add(ctl);