JavaScript Application Cookbook

Potential Extension: Adding Attributes to the Template

Big applications can always be made bigger. This section is devoted to showing you how to add attributes to the image template, giving you greater control over the generated code. For the sake of simplicity, I’ll show you how to add the IMG attributes HSPACE and VSPACE. The procedure involves these six steps:

1. Add the new fields in the default template.

2. Create an array for its values in setArrays().

3. Capture the new default values.

4. Add text fields in the image template in generateEntryForm().

5. Reference and assign the new attribute values in genJavaScript().

6. Generate the HTML required to display the attributes in genJavaScript().

JavaScript Technique: String Replacement with JavaScript 1.1 and 1.2

JavaScript 1.2 brought with it many cool new features. One of those is the ability to use regular expressions for string matching and replacing. Functions pathPrep() and purify() perform a simple but powerful method of replacing, using JavaScript 1.2. This is a great for JavaScript 1.2 capable browsers, but Netscape 3.x is still used in significant numbers. Here is a function that performs string replacement in JavaScript 1.1 using methods of the Array object:

function replacev11(str, oldSubStr, newSubStr) {
  var newStr = str.split(oldSubStr).join(newSubStr);
  return newStr;
  }

This function takes a string, creates an array of elements split() according to the substring you want to remove (oldSubStr), then returns a string made by ...