在asp.net 2.0下,gridview是十分方便的了,加一个DATASOURCE系列的控件的话,就可以马上和gridview绑定,十分方便。但其实也可以
使用datatable或者dataview的,这个时候就不是用datasource系列控件了。下面讲下如何在asp.net 2.0下,实现gridview控件的翻页,各列排序,
编辑的功能。
首先,我们读取的是northwind数据库中的employee表。放置一个gridview后,添加几个绑定的列,代码如下
<asp:GridView ID=\"GridView1\" runat=\"server\" AllowPaging=\"True\" AllowSorting=\"True\"
AutoGenerateColumns=\"False\" CellPadding=\"4\" ForeColor=\"#333333\" GridLines=\"None\"
Width=\"100%\" DataKeyNames=\"EmployeeID\" OnPageIndexChanging=\"GridView1_PageIndexChanging\" OnRowEditing=\"GridView1_RowEditing\" OnRowUpdating=\"GridView1_RowUpdating\" OnSorting=\"GridView1_Sorting\" PageSize=\"3\" OnRowCancelingEdit=\"GridView1_RowCancelingEdit\" OnRowCommand=\"GridView1_RowCommand\">
<FooterStyle BackColor=\"#990000\" Font-Bold=\"True\" ForeColor=\"White\" />
<Columns>
<asp:BoundField DataField=\"employeeid\" HeaderText=\"Employee ID\" ReadOnly=\"True\" />
<asp:BoundField DataField=\"firstname\" HeaderText=\"First Name\" SortExpression=\"firstname\" />
<asp:BoundField DataField=\"lastname\" HeaderText=\"Last Name\" SortExpression=\"lastname\" />
<asp:CommandField ShowEditButton=\"True\" />
</Columns>
<RowStyle BackColor=\"#FFFBD6\" ForeColor=\"#333333\" />
<SelectedRowStyle BackColor=\"#FFCC66\" Font-Bold=\"True\" ForeColor=\"Navy\" />
<agerStyle BackColor=\"#FFCC66\" ForeColor=\"#333333\" HorizontalAlign=\"Center\" />
<HeaderStyle BackColor=\"#990000\" Font-Bold=\"True\" ForeColor=\"White\" />
<AlternatingRowStyle BackColor=\"White\" />
</asp:GridView>
首先,我们要实现分页,把AllowPaging设置为true,并设置每页的分页条数,最后在codebehind中写入
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
BindGrid();
}
为了实现每列都可以自动点击排序,可以设置allowsorting=true,然后设置OnSorting=\"GridView1_Sorting\",其中gridview_sorting
代码为
protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
{
ViewState[\"sortexpression\"] = e.SortExpression;
if (ViewState[\"sortdirection\"] == null)
{
ViewState[\"sortdirection\"] = \"asc\";
}
else
{
if (ViewState[\"sortdirection\"].ToString() == \"asc\")
{
ViewState[\"sortdirection\"] = \"desc\";
}
else
{
ViewState[\"sortdirection\"] = \"asc\";
}
}
BindGrid();
}
很明显,设置viewsate来保存每次排序时的顺序,上面的相信很容易理解。
最后,实现编辑功能,因为在aspx页面中已经设置了OnRowEditing=\"GridView1_RowEditing\",其中GridView1_RowEditing的代码为
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
int empid;
string fname, lname;
empid = int.Parse(GridView1.Rows[e.RowIndex].Cells[0].Text);
fname = ((TextBox)GridView1.Rows[e.RowIndex].Cells[1].Controls[0]).Text;
lname = ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text;
SqlConnection cnn = new SqlConnection(@\"data source=localhost;initial catalog=northwind;user id=sa;password=123456\");
cnn.Open();
SqlCommand cmd = new SqlCommand(\"update employees set firstname=@fname,lastname=@lname where employeeid=@empid\", cnn);
cmd.Parameters.Add(new SqlParameter(\"@fname\",fname));
cmd.Parameters.Add(new SqlParameter(\"@lname\", lname));
cmd.Parameters.Add(new SqlParameter(\"@empid\", empid));
cmd.ExecuteNonQuery();
cnn.Close();
GridView1.EditIndex = -1;
BindGrid();
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
BindGrid();
}
protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
GridView1.EditIndex = -1;
BindGrid();
}
可以看到,上面的代码和asp.net 1.1版本的其实原理是差不多的。最后,bindgrid()的过程很简单,为绑定咯
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(\"select * from employees\", @\"data source=localhost;initial catalog=northwind;user id=sa;password=123456\");
da.Fill(ds,\"employees\");
DataView dv = ds.Tables[0].DefaultView;
if (ViewState[\"sortexpression\"] != null)
{
dv.Sort = ViewState[\"sortexpression\"].ToString() + \" \" + ViewState[\"sortdirection\"].ToString();
}
GridView1.DataSource=dv;
GridView1.DataBind();
这里gridview绑定的是dataview,并且用dv.sort设定了每次排序的顺序,也就是说,每次排序后其顺序都是保持不变的。
当然最后是page_load事件咯
protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
BindGrid();
}
} |