User-922313987 posted
Hi Guys,
I want to create a custom server control which inherits from DataList with linkbuttons to handle paging in VS 2005. But when the datasource of datalist is set, The page navigation linkbuttons don't
contain "dopostback()" script and the event doesn't fire . how to deal with it?
thanks
<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
1 [ToolboxData("<{0}:CustomDataList runat=server></{0}:CustomDataList>")]
2 public class CustomDataList : DataList, INamingContainer
3 {
4
5 private event EventHandler _onDataListDataBind;
6 private PagedDataSource pageSource;
7 private Label ctl_lbl_TotalComments, ctl_lbl_PageNumber;
8 private TextBox ctl_tbx_PageNumber;
9 private LinkButton ctl_lbtn_PrevPage, ctl_lbtn_NextPage;
10
11
12 [Bindable(true)]
13 [Category("Data")]
14 [DefaultValue("")]
15 [Localizable(true)]
16 [Browsable(true)]
17 public event EventHandler OnDataListDataBind
18 {
19 add { _onDataListDataBind += value; }
20 remove { _onDataListDataBind -= value; }
21 }
22
23 public override object DataSource
24 {
25 get
26 {
27 return base.DataSource;
28 }
29 set
30 {
31 if (pageSource == null)
32 {
33 pageSource = new PagedDataSource();
34 pageSource.DataSource =(System.Collections.IEnumerable)value;
35 pageSource.AllowPaging = true;
36 pageSource.PageSize = 1;
37 pageSource.CurrentPageIndex = Convert.ToInt32(ctl_tbx_PageNumber.Text) - 1;
38 }
39 base.DataSource = pageSource;
40 }
41 }
42
43 protected LinkButton PrevPageLinkButton
44 {
45 get { EnsureChildControls(); return ctl_lbtn_PrevPage; }
46 }
47
48 protected LinkButton NextPageLinkButton
49 {
50 get { EnsureChildControls(); return ctl_lbtn_NextPage; }
51 }
52
53 protected TextBox PageNumTextBox
54 {
55 get { EnsureChildControls(); return ctl_tbx_PageNumber; }
56 }
57
58 protected override void OnLoad(EventArgs e)
59 {
60 EnsureChildControls();
61 if (!this.Page.IsPostBack)
62 {
63 //ViewState["PageNumber"] = 1;
64 BindData(1);
65 }
66 }
67
68 protected override void CreateChildControls()
69 {
70 Controls.Clear();
71
72 ctl_lbl_TotalComments = new Label();
73 ctl_lbl_TotalComments.Text = "0";
74 Controls.Add(ctl_lbl_TotalComments);
75
76 ctl_lbl_PageNumber = new Label();
77 ctl_lbl_PageNumber.Text = "1";
78 Controls.Add(ctl_lbl_PageNumber);
79
80 ctl_lbtn_PrevPage = new LinkButton();
81 ctl_lbtn_PrevPage.Text = "<<";
82 ctl_lbtn_PrevPage.CssClass = "linkbold0066ff fontS14";
83 ctl_lbtn_PrevPage.Click += new EventHandler(ctl_lbtn_PrevPage_Click);
84 Controls.Add(ctl_lbtn_PrevPage);
85
86 ctl_lbtn_NextPage = new LinkButton();
87 ctl_lbtn_NextPage.Text = ">>";
88 ctl_lbtn_NextPage.CssClass = "linkbold0066ff fontS14";
89 ctl_lbtn_NextPage.Click += new EventHandler(ctl_lbtn_NextPage_Click);
90 Controls.Add(ctl_lbtn_NextPage);
91
92 ctl_tbx_PageNumber = new TextBox();
93 ctl_tbx_PageNumber.MaxLength = 3;
94 ctl_tbx_PageNumber.AutoPostBack = true;
95 ctl_tbx_PageNumber.Text = "1";
96 ctl_tbx_PageNumber.CssClass = "pagerinput";
97 ctl_tbx_PageNumber.TextChanged += new EventHandler(ctl_tbx_PageNumber_TextChanged);
98 Controls.Add(ctl_tbx_PageNumber);
99
100 ChildControlsCreated = true;
101 ClearChildControlState();
102 }
103
104 void ctl_lbtn_NextPage_Click(object sender, EventArgs e)
105 {
106 int _nextPageNumber = Convert.ToInt32(ctl_tbx_PageNumber.Text) + 1;
107 BindData(_nextPageNumber);
108 }
109
110 void ctl_lbtn_PrevPage_Click(object sender, EventArgs e)
111 {
112 int _prevPageNumber = Convert.ToInt32(ctl_tbx_PageNumber.Text) - 1;
113 BindData(_prevPageNumber);
114 }
115
116 void ctl_tbx_PageNumber_TextChanged(object sender, EventArgs e)
117 {
118 int _customPageNumber = Convert.ToInt32(ctl_tbx_PageNumber.Text);
119 BindData(_customPageNumber);
120 }
121
122 private void BindData(int pageNum)
123 {
124 if (_onDataListDataBind != null)
125 {
126 _onDataListDataBind(null, new EventArgs());
127
128 ctl_lbl_TotalComments.Text = pageSource.DataSourceCount.ToString();
129 ctl_lbl_PageNumber.Text = pageSource.PageCount.ToString();
130 ctl_tbx_PageNumber.Text = pageNum.ToString();
131
132 if (!pageSource.IsFirstPage)
133 {
134 ctl_lbtn_PrevPage.Enabled = true;
135 }
136 else
137 {
138 ctl_lbtn_PrevPage.Enabled = false;
139 }
140
141 if (!pageSource.IsLastPage)
142 {
143 ctl_lbtn_NextPage.Enabled = true;
144 }
145 else
146 {
147 ctl_lbtn_NextPage.Enabled = false;
148 }
149 }
150 }
151
152 protected override void Render(HtmlTextWriter writer)
153 {
154 RenderContents(writer);
155 writer.WriteBreak();
156 ctl_lbl_TotalComments.RenderControl(writer);
157 writer.Write("Records");
158 writer.WriteBreak();
159 PrevPageLinkButton.RenderControl(writer);
160 PageNumTextBox.RenderControl(writer);
161 writer.Write(" of ");
162 ctl_lbl_PageNumber.RenderControl(writer);
163 NextPageLinkButton.RenderControl(writer);
164 }
165 }
