to avoid any erroneous data to be inserted into the database. So let us learn some basics because I have written this article only focusing on beginners and students. Example I hope you now understand the basics of validation in Java Script, now let us create the one sample web application that demonstrates how to do validation.
In this article we will learn about client-side validation that is done using Java Script. In the preceding syntax function is the keyword provided by the Java Script to declare a function and the Vildate Data() is the function name, now write the code inside the function as in the following.
The validation control classes are inherited from the Base Validator class hence they inherit its properties and methods.
Therefore, it would help to take a look at the properties and the methods of this base class, which are common for all the validation controls: The Regular Expression Validator allows validating the input text by matching against a pattern of a regular expression.
If we get the user input with validation, then chances are that we are sending the wrong data.
Whenever the user gives the input, it must always be validated before sending it across to various layers of an application.
The client side validation is accomplished through the Client Validation Function property.
Importantance of returning false It's very important to use the return false statement after the condition block that return false so if validation determines that the business requirements are not met then the form cannot be submitted.aspdotnet-suresh offers C#articles and tutorials,csharp dot net,articles and tutorials, VB.Basically what it's saying is that validation will succeed if any other value than the 1 set in Initial Value is selected in the dropdownlist.Client side validation Validation done in the browser before sending the form data to the server using Java Script, j Query and VBScript is called client-side validation. Let us first create the web application with two web pages We are adding two web pages because our requirement is, in the first web page there is form data to be filled in by the user and only after validating the form data, the form will be redirected to the next page.Server Side Validation Validation done at the server level after sending the form data to the server but before entering the data into the database is called server-side validation. The first page source code Look at the preceding source code closely; see the id's of controls that play the important role in Java Script validation by reading the ASP. The design view of the preceding source code will look as in the following: I hope you have created the same form as above for demonstration purposes. Net controls values in Java Script are as: There are three main methods shown in the above image in the red square to read the ASP.