barcode vb.net Validating User Input with Ajax and PHP in Java

Creator Data Matrix in Java Validating User Input with Ajax and PHP

Validating User Input with Ajax and PHP
Data Matrix ECC200 Generation In Java
Using Barcode maker for Java Control to generate, create DataMatrix image in Java applications.
Read ECC200 In Java
Using Barcode recognizer for Java Control to read, scan read, scan image in Java applications.
if($_REQUEST["number"] == "") { $errors[] = "<font color='red'>Please enter your age</font>"; } if(strcmp($_REQUEST["number"], strval(intval($_REQUEST["number"])))) { $errors[] = "<font color='red'>Please enter an integer</font>"; } } function display_errors() { global $errors; foreach ($errors as $error){ echo $error, "<br>"; } } function process_data() { echo "Thank you Your age is "; echo $_REQUEST["number"]; } function display_welcome() { echo "<form method='post' action='checkdataintegerphp'>"; echo "Please enter your age"; echo "<br>"; echo "<input name='number' type='text'>"; echo "<br>"; echo "<br>"; echo "<input type='submit' value='Submit'>"; echo "<input type='hidden' name='welcome_already_displayed' value='data'>"; echo "</form>"; } > </center> </body> </html>
Bar Code Generation In Java
Using Barcode printer for Java Control to generate, create barcode image in Java applications.
Scanning Bar Code In Java
Using Barcode scanner for Java Control to read, scan read, scan image in Java applications.
As you can see, the code is substantially the same as that for checkdataphp, indicating that you can readily modify our PHP validation technique to check for the kinds of errors you want The checkdataintegerphp application appears in Figure 11-13 If the data you enter is not an integer, you ll get an error, as you see in Figure 11-14 Beautiful
Data Matrix Creation In C#
Using Barcode drawer for .NET framework Control to generate, create ECC200 image in VS .NET applications.
Make DataMatrix In .NET Framework
Using Barcode creation for ASP.NET Control to generate, create Data Matrix 2d barcode image in ASP.NET applications.
Ajax: A Beginner s Guide
Data Matrix 2d Barcode Encoder In .NET
Using Barcode drawer for Visual Studio .NET Control to generate, create Data Matrix image in VS .NET applications.
Encoding Data Matrix ECC200 In Visual Basic .NET
Using Barcode printer for .NET framework Control to generate, create ECC200 image in .NET framework applications.
Figure 11-13
Encode 2D Barcode In Java
Using Barcode printer for Java Control to generate, create Matrix 2D Barcode image in Java applications.
Encode Code 128 Code Set C In Java
Using Barcode drawer for Java Control to generate, create Code 128 image in Java applications.
Displaying the welcome page
Code 39 Full ASCII Drawer In Java
Using Barcode creator for Java Control to generate, create USS Code 39 image in Java applications.
Generating EAN / UCC - 14 In Java
Using Barcode maker for Java Control to generate, create EAN / UCC - 13 image in Java applications.
Figure 11-14
MSI Plessey Creator In Java
Using Barcode maker for Java Control to generate, create MSI Plessey image in Java applications.
Create Code 128A In Visual Basic .NET
Using Barcode generation for .NET framework Control to generate, create Code 128 image in Visual Studio .NET applications.
Displaying an error
Decode GS1 - 12 In VB.NET
Using Barcode scanner for .NET framework Control to read, scan read, scan image in .NET framework applications.
Making Barcode In .NET Framework
Using Barcode creation for ASP.NET Control to generate, create barcode image in ASP.NET applications.
Validating Text
Paint Bar Code In None
Using Barcode creator for Font Control to generate, create barcode image in Font applications.
Create Code 3 Of 9 In Java
Using Barcode drawer for Eclipse BIRT Control to generate, create Code 3/9 image in BIRT applications.
You can even check to make sure text entries are in the right format with PHP s regular expression checking Regular expressions let you examine the format of text to make sure it matches a template you supply see http://perldocperlorg/perlrehtml for all the details
Print Linear In VB.NET
Using Barcode maker for .NET Control to generate, create Linear image in VS .NET applications.
UPC-A Supplement 2 Generator In None
Using Barcode drawer for Software Control to generate, create UPC-A Supplement 2 image in Software applications.
11:
Validating User Input with Ajax and PHP
Say, for example, that you want to make sure that the user enters their social security number, which in digit terms is xxx-xx-xxxx You can do that with PHP s preg_match function, which, using the fact that digits are represented by \d in regular expressions, would make your validate_data function look like this:
function validate_data() { global $errors; if(!preg_match('/^\d\d\d-\d\d-\d\d\d\d$/', $_REQUEST["data"])){ $errors[] = "<font color='red'>Please enter a social security number" </font>"; } }
This page intentionally left blank
Using the HTML DOM and Ajax
Copyright 2009 by The McGraw-Hill Companies Click here for terms of use
Ajax: A Beginner s Guide
Key Skills & Concepts
Introducing the DOM Appending elements using the DOM Replacing elements using the DOM Handling Ajax timeouts
eb pages can be viewed as collections of objects using the HTML DOM (Document Object Model), which gives you the power to access everything in a page In Ajax, knowing how to update your web pages with newly downloaded data is essential You ve already seen that the basic model is to use a <div> or <span> element and to simply replace the contents of that element with the new data:
function getData(dataSource, divID) { if(XMLHttpRequestObject) { var obj = documentgetElementById(divID); XMLHttpRequestObjectopen("GET", dataSource); XMLHttpRequestObjectonreadystatechange = function() { if (XMLHttpRequestObjectreadyState == 4 && XMLHttpRequestObjectstatus == 200) { objinnerHTML = XMLHttpRequestObjectresponseText; } }
Beyond the basic model, another option is to use dynamic HTML, as you saw in 8 There, you found new ways of inserting new data into web pages, such as using the insertAdjacentHTML method:
<html> <head> <title> Updating a Page With insertAdjacentHTML </title> <script language="JavaScript"> function addHTML() { targetDivinsertAdjacentHTML("AfterEnd", "<p><input type=text value='Hello there'> See A new text field</p>"); }
12:
</script> </head>
Using the HTML DOM and Ajax
It turns out that there are additional techniques that you can use to modify a web page without refreshing that web page, and those techniques are wrapped up into the HTML DOM The DOM provides a way of looking at the contents of a web page as a collection of objects, complete with built-in methods and properties, all available for you to use in your Ajax applications
Getting to Know the DOM
As mentioned, the DOM treats a web page as a collection of objects The easiest way to explain this is through an example, so let s start with a likely looking HTML web page:
<html> <head> <title> The Report </title> </head> <body> <h1> All quiet on the Western front </h1> </body> <html>
This is just a plain web page with a title that will appear in the browser s title bar and some text that will appear in an <h1> header But looked at in DOM terms, the elements of this simple web page make up a collection of objects, arranged into a tree structure Here s what this web page looks like in DOM terms, as a tree of nodes:
<html> | ----------------------------------| | | | <head> <body> | | | | <title> <h1> | | | | The Report All quiet on the Western front
Copyright © OnBarcode.com . All rights reserved.