Find literals in aspx page

Question

I have 42 Literals on my web page and their IDs like ltr1,ltr2,...,ltr41,ltr42. I want to change their text property in a for loop.

hereis the html code:

<table class="calendar">
    <tr>
        <td>
            <div class="day">
                <asp:Literal ID="day1" runat="server">
                </asp:Literal></div>
        </td>
    </tr>
 </table>

c#

for(int i=1;i<43;i++)
{
    ("ltr"+i).Text="something"; //I don't know which method I must use, so wrote like this
}

How can I do this?

Answer 1

You may load all the literals in a collection using OfType and later you can modify their text property.

var literals = this.Page.Controls.OfType<Literal>();
foreach (Literal literal in literals)
{
    literal.Text = "Your Text";
}

EDIT:

Since you have control inside another control on the page, you need to do a nested search for controls. You can try the following extension methods. Taken from this post .

First create a class for extension method as:

public static class ExtensionMethod
{
    public static IEnumerable<Control> FindAll(this ControlCollection collection)
    {
        foreach (Control item in collection)
        {
            yield return item;

            if (item.HasControls())
            {
                foreach (var subItem in item.Controls.FindAll())
                {
                    yield return subItem;
                }
            }
        }
    }

    public static IEnumerable<T> FindAll<T>(this ControlCollection collection) where T : Control
    {
        return collection.FindAll().OfType<T>();
    }
}

Later you can use it like:

protected void Button1_Click(object sender, EventArgs e) 
{
    var literals = this.Controls.FindAll<Literal>();
    foreach (Literal literal in literals)
    {
        literal.Text = "Your Text";
    }
}

Answer 2

when you are using master page that time your control didn't got directly from Page.FindControl() method. so you need to go 1 level deep to find control from asp:ContentPlaceHolder id's.

Master Page:

<asp:ContentPlaceHolder ID="cphContent" runat="server" />

aspx Page :

<asp:Content ID="Content2" ContentPlaceHolderID="cphContent" runat="server">
    <asp:Literal ID="day1" runat="server"></asp:Literal>
</asp:Content>

aspx Page.cs :

var literals = Page.Master.FindControl("cphContent").Controls.OfType<Literal>();
foreach (Literal literal in literals)
{
     literal.Text = "Your Text";
}

Answer 3

How about the Page.FindControl() method?

for(int i=1;i<43;i++)
{
    Literal li = (Literal)Page.FindControl("ltr"+i);
    li.Text="something";
}

Answer 4

You need to do a recursive lookup of the controls on the page. By performance .net dont to this by default.

Read more about Recursive FindControl here

Answer 5

you can do this, wrap a at the top level like this:

    <div id="Content" runat="Server">

    <table border="0" cellspacing="0" cellpadding="0" width="100%">
        <tr>
            <td><asp:Literal ID="Literal1" runat="server"></asp:Literal></td>
            <td><asp:Literal ID="Literal2" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal3" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal4" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal5" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal6" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal7" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal8" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal9" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal10" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal11" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal12" runat="server"></asp:Literal></td>
<td><asp:Literal ID="Literal13" runat="server"></asp:Literal></td>

        </tr>
    </table>

    </div>

and you can code like this :

        for (int i = 1; i < 10; i++)
        {
            Literal li = (Literal)Content.FindControl("Literal"+i);
        }