WMLScript Tutorial
WMLScript (Wireless Markup Language Script) is the partner of WML. It is a client-side scripting language that is very similar to JavaScript. Our WMLScript tutorial begins with an overview of WMLScript and its language rules. Then we will look at functions and variables. You can learn how to define functions, how to declare variables, etc. Operators, conditional and looping statements will be covered afterwards. The WMLScript standard library contains a lot of useful functions. We will go through some of the commonly used ones. At the end of the WMLScript tutorial, we will demonstrate how to write scripts to validate forms and submit data to the WAP server.
Plenty of code examples are given in the WMLScript tutorial to help you understand the concepts and techniques.
Table of Contents
WMLScript Introduction
What is WMLScript?
WMLScript MIME Type and File Extension
Hello World WMLScript Example
Compiling WMLScript Code
WMLScript Compilers
WMLScript Language Rules
Semicolons at the End of WMLScript Statements
Whitespaces in WMLScript
Case Sensitivity in WMLScript
Comments in WMLScript
String Literals in WMLScript
Defining WMLScript Functions
The extern Keyword
WMLScript Function Naming Conventions
WMLScript Function Arguments
The return Statement
Calling WMLScript Functions
Calling a Function Located in the Same WMLScript File
Calling a Function Located in a Different WMLScript File
Calling a Function from a WML Card
Passing Arguments to Functions
WMLScript Variables
Declaring WMLScript Variables Using the var Keyword
WMLScript Variable Naming Conventions
Scope and Lifetime of WMLScript Variables
WMLScript Data Types
WMLScript Variables Vs WML Variables
Using WMLScript to Set the Value of a WML Variable
Using WMLScript to Obtain the Value of a WML Variable
Passing Arguments to Functions By Value and By Reference
WMLScript Operators
WMLScript Arithmetic Operators - Performing Math Operations
Basic Math Operations - Addition, Subtraction, Multiplication, Division, Finding Remainders
Pre/Post Increment and Decrement
Bitwise Operations - Dealing with Binary Representations of Numbers
WMLScript Assignment Operators - Assigning Values to Variables
WMLScript Logical Operators - Performing Boolean Operations
WMLScript Comparison Operators - Checking Two Values against a Certain Condition
WMLScript Conditional Operator - Choosing One Expression out of Two to Evaluate Depending on a Condition
WMLScript String Operators - Concatenating Strings
WMLScript typeof Operator - Finding Data Types of Variables
WMLScript isvalid Operator - Finding if a Variable is of the Invalid Data Type
WMLScript Conditional Statements
if Statement
WMLScript Looping Statements
while Statement
for Statement
break Statement: Quitting a Loop
continue Statement: Quitting Current Iteration of a Loop
WMLScript Standard Libraries Overview
How to Call a Function in the WMLScript Standard Libraries
WMLScript WMLBrowser Standard Library
Going Forwards / Backwards to WML Cards: go() and prev() Functions
Clearing Variables and URL History: newContext() Function
Getting the Current WML Card's URL: getCurrentCard() Function
Getting and Setting WML Variable Values: getVar() and setVar() Functions
Refreshing the Current Card on the WML Browser: refresh() Function
WMLScript Dialogs Standard Library
Displaying Messages on the Screen of Wireless Devices: alert() Function
Displaying Confirmation Messages on the Screen of Wireless Devices: confirm() Function
Displaying Input Fields and Getting Data from Users: prompt() Function
WMLScript String Standard Library
Getting the Character at a Certain Index in a String: charAt() Function
Getting the Number of Characters in a String: length() Function
Removing All Leading and Trailing Whitespaces of a String: trim() Function
Finding if a Certain Substring Exists in a String: find() function
Replacing a Substring with Another Substring: replace() Function
Manipulating Elements in Strings
Getting the Number of Elements in a String: elements() Function
Getting the Element at a Certain Index in a String: elementAt() Function
Inserting an Element at a Certain Position in a String: insertAt() Function
Removing the Element at a Certain Index in a String: removeAt() Function
Replacing an Element at a Certain Index with Another Element: replaceAt() Function
Arrays in WMLScript
Declaration of Arrays
Assigning Elements to an Array
Getting Elements of an Array
Changing the Value of an Array Element
WMLScript Float Standard Library
Rounding a Numeric Value: round() Function
Truncating the Fractional Part of a Numeric Value: int() Function
Raising a Numeric Value to the Power of Another Numeric Value: pow() Function
Calculating the Square Root of a Numeric Value: sqrt() Function
Calculating the Ceiling of a Numeric Value: ceil() Function
Calculating the Floor of a Numeric Value: floor() Function
WMLScript Lang Standard Library
Generating Random Numbers: seed() and random() Functions
Finding the Character Set Supported by the WMLScript Interpreter of a Mobile Device: characterSet() Function
Checking Whether Mobile Devices Support Floating-point Numbers and Operations: float() Function
Calculating the Absolute Value of a Numeric Value: abs() Function
Checking Whether the Conversion of a String into an Integer is Possible: isInt() Function
Converting a String to an Integer: parseInt() Function
Checking Whether the Conversion of a String into a Floating-point Number is Possible: isFloat() Function
Converting a String to a Floating-point Number: parseFloat() Function
WMLScript URL Standard Library
Getting the Current WMLScript Document's URL: getBase() Function
Escaping and Unescaping Special Characters in URLs: escapeString() and unescapeString() Functions
Extracting the Query String of an URL: getQuery() Function
Extracting Query Parameters of an URL
WMLScript Example: Validating Form Data
Retrieving Form Data and Removing Leading and Trailing Whitespaces
Checking Whether All Required Fields Has been Filled
Checking the Length of Password
Validating Email Address
Validating Date
Submitting Form Data to the WAP Server with WMLScript
At the Server-side
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