asp.net webform自定义分页控件
做web开发一直用到分页控件，自己也动手实现了个，使用用户自定义控件。
翻页后数据加载使用委托，将具体实现放在在使用分页控件的页面进行注册。
有图有真相，给个直观的认识：
自定义分页控件前台代码：
自定义分页控件后台代码：
private const string viewStateCurrentPageIndex = "CurrentPageIndex";
private const string viewStateRecordCount = "RecordCount";
public delegate void PageChangedHandle();
public event PageChangedHandle OnPageChanged;
public int PageSize
{
get
{
return Convert.ToInt32(ddlPageSize.SelectedValue);
}
}
public int CurrentPageIndex
{
set
{
ViewState[viewStateCurrentPageIndex] = value;
}
get
{
if (ViewState[viewStateCurrentPageIndex] == null)
{
ViewState[viewStateCurrentPageIndex] = 1;
}
return Convert.ToInt32(ViewState[viewStateCurrentPageIndex]);
}
}
public int RecordCount
{
get
{
if (ViewState[viewStateRecordCount] == null)
{
ViewState[viewStateRecordCount] = 0;
}
return Convert.ToInt32(ViewState[viewStateRecordCount]);
}
set
{
ViewState[viewStateRecordCount] = value;
}
}
private int TotalNumberOfPages
{
get
{
return RecordCount % PageSize == 0 ? RecordCount / PageSize : (RecordCount / PageSize) + 1;
}
}
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
}
}
protected void labFirstPage_Click(object sender, EventArgs e)
{
CurrentPageIndex = 1;
this.DataBind();
}
protected void labPreviousPage_Click(object sender, EventArgs e)
{
CurrentPageIndex -= 1;
this.DataBind();
}
protected void labNextPage_Click(object sender, EventArgs e)
{
CurrentPageIndex += 1;
this.DataBind();
}
protected void labLastPage_Click(object sender, EventArgs e)
{
CurrentPageIndex = TotalNumberOfPages;
this.DataBind();
}
protected void btnGo_Click(object sender, EventArgs e)
{
int pageNum = 1;
bool isNum = Int32.TryParse(txtPageNum.Text, out pageNum);
if (isNum)
{
CurrentPageIndex = Math.Min(pageNum, TotalNumberOfPages);
}
this.DataBind();
}
protected void ddlPageSize_SelectedIndexChanged(object sender, EventArgs e)
{
CurrentPageIndex = 1;
this.DataBind();
}
protected override void DataBind(bool raiseOnDataBinding)
{
BindPager();
base.DataBind(raiseOnDataBinding);
if (OnPageChanged != null)
{
OnPageChanged();
}
}
private void BindPager()
{
labCurrentPageIndex.Text = CurrentPageIndex.ToString();
labTotalNumberOfPages.Text = TotalNumberOfPages.ToString();
labRecordCount.Text = RecordCount.ToString();
SetNavigateEnabled();
}
private void SetNavigateEnabled()
{
txtPageNum.Text = CurrentPageIndex.ToString();
labFirstPage.Enabled = true;
labPreviousPage.Enabled = true;
labNextPage.Enabled = true;
labLastPage.Enabled = true;
labFirstPage.CssClass = "font-blue";
labPreviousPage.CssClass = "font-blue";
labNextPage.CssClass = "font-blue";
labLastPage.CssClass = "font-blue";
if (CurrentPageIndex == 1)
{
labFirstPage.Enabled = false;
labPreviousPage.Enabled = false;
labFirstPage.CssClass = "gray";
labPreviousPage.CssClass = "gray";
}
if (CurrentPageIndex == TotalNumberOfPages)
{
labNextPage.Enabled = false;
labLastPage.Enabled = false;
labNextPage.CssClass = "gray";
labLastPage.CssClass = "gray";
}
if (RecordCount == 0)
{
labFirstPage.Enabled = false;
labPreviousPage.Enabled = false;
labFirstPage.CssClass = "gray";
labPreviousPage.CssClass = "gray";
labNextPage.Enabled = false;
labLastPage.Enabled = false;
labNextPage.CssClass = "gray";
labLastPage.CssClass = "gray";
}
}
当前页码、总共多少条记录使用ViewState记录状态信息，因为导航控件会引起回发刷新。
分页后的数据加载，使用事件。
事件的具体实现放在使用分页控件的具体页面中，进行事件的注册。
测试分页控件的前台页面：
测试分页控件的后台代码：
private const string dtSourceViewStateKey = "dtSourceViewStateKey";
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
BindData(true);
}
Pager.OnPageChanged += OnPageChanged;
}
private void BindData(bool bindRecordCount)
{
DataTable dtSource = GetDataSource();
var source = dtSource.AsEnumerable();
if (!string.IsNullOrEmpty(txtContent.Text.Trim()))
{
source = source.Where(w => w.Field("text").Contains(txtContent.Text.Trim()));
}
if (bindRecordCount)
{
Pager.RecordCount = source.Count();
Pager.CurrentPageIndex = 1;
Pager.DataBind();
}
gvList.DataSource = source
.Skip((Pager.CurrentPageIndex - 1) * Pager.PageSize)
.Take(Pager.PageSize)
.Select(r => new { id = r["id"].ToString(), text = r["text"].ToString() })
.ToList();
gvList.DataBind();
}
private void OnPageChanged()
{
BindData(false);
}
private DataTable InitDataTable()
{
DataTable dtSource = new DataTable();
DataColumn id = new DataColumn("id");
id.AutoIncrement = true;
id.AutoIncrementSeed = 1;
dtSource.Columns.Add(id);
dtSource.Columns.Add("text");
for (int i = 1; i <= 1000; i++)
{
DataRow dr = dtSource.NewRow();
dr["text"] = "内容" + i;
dtSource.Rows.Add(dr);
}
return dtSource;
}
private DataTable GetDataSource()
{
if (ViewState[dtSourceViewStateKey] == null)
{
ViewState[dtSourceViewStateKey] = InitDataTable();
}
return ViewState[dtSourceViewStateKey] as DataTable;
}
protected void btnQuery_Click(object sender, EventArgs e)
{
BindData(true);
}
在Page_Load中注册翻页后的事件。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持中文源码网。