DropDownList和dataGrid联动后的分页出错，请达人指点....

[ice2927276]

页面有DropDownList和DataGrid控件，已用dropdownlist的AutoPostBack回传功能实现了联动邦定在datagrid上，datagrid分页也没有问题，但是当datagrid的页码不在第一页时（也就是currentPageIndex>1时），改取dropdownlist的值的化，就会出现错误提示："无效的 CurrentPageIndex 值。它必须大于等于 0 且小于 PageCount。 "我想可能是重新邦定时CurrentPageIndex的取值不对造成的，要怎么解决呢??

apx代码（由于太多，只列相关部份）:
<asp:DropDownList ID="ddlShowType" runat="server" AutoPostBack="True" OnSelectedIndexChanged="ddlShowType_SelectedIndexChanged">
</asp:DropDownList>
<asp:DataGrid ID="dgShowTodayInput" runat="server" AutoGenerateColumns="False" AllowPaging="True" PageSize="5" OnPageIndexChanged="dgShowTodayInput_PageIndexChanged" >
<PagerStyle NextPageText="下一页" PrevPageText="上一页" Mode="NumericPages" />
</asp:DataGrid>

aspx.cs代码:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
this.bindddlType();//调用邦定ddlShowType
this.bindShowTodayInput();//调用邦定datagrid
}
}
///邦定ddlShowType
private void bindddlType()
{
DataSet ds = db.returnDs("select insuID,insuName from insuType");
this.ddlShowType.DataSource = ds.Tables["Table"];
this.ddlShowType.DataValueField = "insuID";
this.ddlShowType.DataTextField = "insuName";
this.ddlShowType.DataBind();
}
//当dropdownList值改变时,重新邦定datagrid
protected void ddlShowType_SelectedIndexChanged(object sender, EventArgs e)
{
this.bindShowTodayInput();
}
//邦定dataGrid
private void bindShowTodayInput()
{
string phType = this.ddlShowType.SelectedItem.Text;
DataSet ds = db.returnDs("select * from phDetailes where phType='" + phType + "' and ifUse='1'");
this.dgShowTodayInput.DataKeyField = "phID";
this.dgShowTodayInput.DataSource = ds.Tables["Table"];
this.dgShowTodayInput.DataBind();
}
//分页
protected void dgShowTodayInput_PageIndexChanged(object source, DataGridPageChangedEventArgs e)
{
this.dgShowTodayInput.CurrentPageIndex = e.NewPageIndex;
this.bindShowTodayInput();
}

[viva369]

//分页
protected void dgShowTodayInput_PageIndexChanged(object source, DataGridPageChangedEventArgs e)
{
bindShowTodayInput //需要重新绑定数据源，否之e.NewPageIndex为null了
this.dgShowTodayInput.CurrentPageIndex = e.NewPageIndex;
// this.bindShowTodayInput();
dgShowTodayInput.DataBind();
}

[ice2927276]

谢谢两位,二楼的正解,我怎么没想到呢,郁闷,,,,同样谢谢三楼的,虽然我没看懂你写的是怎么回事,

[xiaoqhuang]

//当dropdownList值改变时,重新邦定datagrid
protected void ddlShowType_SelectedIndexChanged(object sender, EventArgs e)
{
this.dgShowTodayInput.CurrentPageIndex=0
this.bindShowTodayInput();
}