ASP.Net: Literal vs Label
I just wanted to hear some authorities on when and where you should use a LITERAL
control over a LABEL
.
As I understand it, the difference is this: A LABEL
can be styled via the <SPAN>
tags that are added.
I personally find the addition of <SPAN>
tags in my HTML to be very annoying and never actually apply styles through ASP, and so LITERAL
s seem to be what should be used most of the time... but I'm concerned there's other considerations or benefits to using a LABEL over it th开发者_高级运维at I'm unaware of.
Is it 100% fine to replace any LABEL
s with LITERAL
s, provided we're not applying styles to them? Are there NO other considerations?
Yep, the main difference is that Literal
controls just render out text, but Label
controls surround it with <span>
tags (Unless you use the AssociatedControlID
property, in which case a Label
control will render a <label>
tag).
So, labels can be styled easier, but if you're just inserting text, literals are the way to go. Literal controls also have a handy property Mode
which governs how the text is rendered. You can have it HTML-encoded, or rendered without any changes, or have any "unsupported markup-language elements" removed.
If you're not applying any styles (e.g. by using Label
's CssClass
property), it will be fine to replace Label
controls with Literal
controls.
When you have code similar to
<asp:Label EnableViewState="false" ID="Label8" runat="server"
AssociatedControlID="txtEmail">Email Address:</asp:Label>
<asp:TextBox ID="txtEmail" runat="server"></asp:TextBox>
It is optimal to use a label element because it will correctly turn it into a html label
element with the correct for
attribute targeting your text box, so that if a user clicks on the label it automatically sets their cursor inside the text field.
Otherwise use the literal unless having the text wrapped in a span
would be beneficial for css styling.
To display simple text, formatted text or HTML text as it is i will start with literal first as its lightweight and does not emit out extra SPAN tags.
See this video which demonstrates about those extra tags.
But we can not apply CSS on a literal , we can not add attributes like Label1.Attributes.Add to a literal. Any container oriented things can not be achieved as literal is not surrounded by a SPAN tag.
It's also sad to see lot of ASP.NET Webform guys by default choose label to display text not knowing that it generates extra SPAN tags which can make your HTML heavy if you have lot's of label.
Difference b/w Label and Literal Control in asp.net
In almost all ways a Literal control is the same as a Label control. Both of these controls are used to display Text on a webform. (The Text property can be set in the HTML or in the code-behind.)
The biggest difference is that the Label control wraps the text in a span
when rendered. Any style that is applied to the Label control, will be rendered using the style
property of the span
.
For example, the following HTML
<asp:Label ID="Label1" runat="server" Text="Label Text"
ForeColor="Red" Font-Bold="true" ></asp:Label>
Will be rendered as
<span id="Label1" style="color:Red;font-weight:bold;">Label Text</span>
A Literal control doesn't output any surrounding tags, so the Text is displayed as is:
For example, the following HTML
<asp:Literal ID="Literal1" runat="server"
Text="Literal Control Text"></asp:Literal>
will be rendered as
Literal Control Text
So if you want to apply any styles to a than use Label control otherwise use the Literal control. Because of this, the Literal control is a light weight control, when compared with the Label control.
FYI: The inheritance hierarchy for Literal control class is (Object => Control => Literal), where as for the Label control, the hierarchy is (Object => Control => WebControl=> Label)
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