/// <summary>
/// 获得排序字符串。
/// </summary>
/// <param name="grid">GridView 对象。</param>
/// <param name="sortExpression">要排序的字段名称。e.SortExpression 属性值。</param>
/// <param name="bindType"></param>
/// <returns>返回拼装好的排序字符串。</returns>
public static string GetSortExpression(GridView grid, string sortExpression, BindPagingGridViewType bindType)
{
string m_sortExpression = "SortExpression";
// strTemp 不为空表示上次排序就是按照这个字段排序的。
string strTemp = grid.Attributes[m_sortExpression];
if (string.IsNullOrEmpty(strTemp))
{
strTemp = string.Empty;
}
switch (bindType)
{
case BindPagingGridViewType.Sorting:
if (string.Compare(strTemp, sortExpression, true) == 0 || strTemp.ToLower().IndexOf(sortExpression) > -1)
{
// 相同一列点击第二次。
if (strTemp.ToLower().IndexOf("desc") > -1)
{
sortExpression = strTemp.ToLower().Replace(" desc", string.Empty);
}
else
{
sortExpression = string.Format("{0} desc", sortExpression);
}
}
break;
case BindPagingGridViewType.Paging:
if (!string.IsNullOrEmpty(strTemp))
{
sortExpression = strTemp;
}
break;
case BindPagingGridViewType.Searching:
break;
}
grid.Attributes[m_sortExpression] = sortExpression;
return(sortExpression);
}
/// <summary>
/// 绑定 GridView 数据，并且导向到指定页码。
/// </summary>
/// <param name="grid">GridView 控件。</param>
/// <param name="dv">DataView 数据源。</param>
/// <param name="pageIndex">默认指定页码。</param>
/// <param name="sortExpression">排序字段。</param>
/// <param name="supportSortViewState">是否支持记录上一次排序表达式。（第一次正序，第二次倒序。）</param>
/// <param name="bindType">枚举类型参数，指定此次调用是翻页调用还是排序调用。</param>
/// <returns></returns>
/// <remarks>如果支持记录上次排序表达式，当指定调用方式为排序掉用是，就支持了表头双击了。如果指定调用方式翻页调用则翻页时能够保持排序。</remarks>
public static bool BindPagingGridView(GridView grid, DataView dv, int pageIndex, string sortExpression, bool supportSortViewState, BindPagingGridViewType bindType)
{
if (grid == null)
{
return(false);
}
bool blnRet = false;
try
{
if (grid.AllowPaging)
{
if (dv.Count > 0)
{
grid.PageIndex = Math.Min(pageIndex, (int)Math.Ceiling(dv.Count / (double)grid.PageSize) - 1);
}
else
{
grid.PageIndex = 0;
}
}
if (pageIndex < 0)
{
pageIndex = 0;
}
if (supportSortViewState)
{
dv.Sort = GetSortExpression(grid, sortExpression, bindType);
}
else if (!string.IsNullOrEmpty(sortExpression))
{
dv.Sort = sortExpression;
}
grid.DataSource = dv;
grid.DataBind();
blnRet = true;
}
catch (Exception ex)
{
throw ex;
}
return(blnRet);
}
