RequiredFieldValidator is the simplest available control in ASP.NET. You can use it to ensure that the associated control is not empty. For example, the control will fail validation if a linked text box doesn’t contain any content or contains spaces. Instead of checking for blank values you can specify a default value using the InitialValue property. In this …
asp.net 2.0
If you want to understand how RangeValidator works, by example, you can develop a simple test web page. This page uses a single Button web control, two TextBox controls and a RangeValidator control that validates the first text box. If validation fails, the RangeValidator control displays an error message, so you should place this control immediately next to …
The CompareValidator control compares a value in one control with a fixed value or, more commonly, a value in another control. You can use this control to check that two text boxes have the same data or that a value in one text box doesn’t exceed a maximum value established in another. The CompareValidator control, like the RangeValidator …
The validation controls are found in the System.Web.UI.WebControls namespace and inherit from the BaseValidator class. This class defines the basic functionality for a validation control. The next table describes its key properties:
Namespace: System.Web.UI.WebControls
Assembly: System.Web (in System.Web.dll)
Property
Description
Supported in .NET version
ControlToValidate
The property is used to identify the control that this validator will check. Each validator can verify …
In most of modern browsers as Internet Explorer, Firefox, Google Chrome and Safari, ASP.NET 4.0 automatically adds JavaScript code for client-side validation. In this case, when the user clicks a CausesValidation button, the same error messages will appear without the page needing to be submitted and returned from the server. This increases the responsiveness of your web page. …
You can use the validator controls, described in the article How validation controls work in ASP.NET 4.0, to verify a page automatically when the user submits it or manually in your code. The first approach is the most common. When using automatic validation, the user receives a normal page and begins to fill in the input controls. When …
Validation controls in ASP.NET 4.0 resolve time consuming and complicated task- verifying user input and reporting errors—and automate it with an elegant, easy-to-use collection of validators. Each validator has its own built-in logic. Some check for missing data, others verify that numbers fall in a predefined range, and so on. In many cases, the validation controls allow you …
XHTML elements are containers that contain pieces of your web page content and used to compose the whole web page. Taken together, these elements define the structure of the web page and they are also the starting point for formatting the web page. The XHTML language defines a small set of elements that you can use. XHTML also …
Every XHTML document starts out with this basic structure (right after the doctype):
<html xmlns=”https://www.w3.org/1999/xhtml”>
<head runat=”server”>
<title>Untitled Page</title>
</head>
<body>
</body>
</html>
When you create a new web form in Visual Studio 2010, this is the structure you start with in which the basic parts are:
– XHTML documents start with the <html> tag …
The doctype directive occupies the second section in .aspx page or ASP.NET web forms and appears just after the page directive, described in the article How to use Page directive in ASP.NET 4.0
The directive indicates the type of markup, HTML, XHTML, etc., used in the web page. This directive is optional, but Visual Studio 2010 adds it automatically. …