今天碰到个怪问题,一直搞到半夜2点多。以下是解决办法:
今天看了一下ListView和DataPager配合做数据分页的教程,感觉很爽很方便,用在自己的项目上面时却出现了问题,具体表现在点击上一页、下一页或者数字跳转页面时通常要点两下才能有反应,而且有时候乱跳页。
我开始测试的代码是这样的:
public partial class ListViewTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
BindData();
}
protected void BindData()
{
DBDataContext db = new DBDataContext();
var ds = db.Category;
ListView1.DataSource = ds;
ListView1.DataBind();
db.Dispose();
}
}
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
BindData();
}
protected void BindData()
{
DBDataContext db = new DBDataContext();
var ds = db.Category;
ListView1.DataSource = ds;
ListView1.DataBind();
db.Dispose();
}
}
出现如开始提及的问题,找了半天原因也没有找到。后来在国外的一个论坛上找到了同病相怜的人,有专家给出了一个解决方案。把Page_Load里的数据绑定移到Page_PreRender中,也就是:
public partial class ListViewTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
//if (!Page.IsPostBack)
// BindData();
}
{
BindData();
}
protected void BindData()
{
DBDataContext db = new DBDataContext();
var ds = db.Category;
ListView1.DataSource = ds;
ListView1.DataBind();
db.Dispose();
}
}
{
protected void Page_Load(object sender, EventArgs e)
{
//if (!Page.IsPostBack)
// BindData();
}
protected void Page_PreRender(object sender, EventArgs e)
{
BindData();
}
protected void BindData()
{
DBDataContext db = new DBDataContext();
var ds = db.Category;
ListView1.DataSource = ds;
ListView1.DataBind();
db.Dispose();
}
}
试了一下分页果然正常了。难道是Page_Load来的太迟?不得而知。另外,还有一种方法同样可行:
public partial class ListViewTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
BindData();
}
{
//BindData();
}
{
DataPager1.SetPageProperties(e.StartRowIndex, e.MaximumRows, false);
BindData();
}
{
DBDataContext db = new DBDataContext();
var ds = db.Category;
ListView1.DataSource = ds;
ListView1.DataBind();
db.Dispose();
}
}
{
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
BindData();
}
protected void Page_PreRender(object sender, EventArgs e)
{
//BindData();
}
protected void ListView1_PagePropertiesChanging(object sender, PagePropertiesChangingEventArgs e)
{
DataPager1.SetPageProperties(e.StartRowIndex, e.MaximumRows, false);
BindData();
}
protected void BindData()
{
DBDataContext db = new DBDataContext();
var ds = db.Category;
ListView1.DataSource = ds;
ListView1.DataBind();
db.Dispose();
}
}