The Eval() Function

The eval() function has been a bit controversial since it was first introduced. JavaScript will always be associated with the eval() function that without it, the application was first thought to be impossible. Developers practically need the function so that they would have a stable application and proceed as planned.

The eval() function is a small but highly significant part of the application in the past few years. In gist, the function provides the needed evaluation of the string and arguments before they are properly implemented in the JavaScript engine. The application is practically optimized with this simple function.

Even though eval() has provided significant advantages in the Ajax or JavaScript based applications, there are some limitations that have created problems when implemented in the client side. The foremost concern of developers when implementing eval() is that it would seem that the function will eventually expose the data related to the application.

As already indicated eval() tries to take a look at the string before they are implemented in the JavaScript engine. This means the data will be exposed before they are being used since they will be closely evaluated. Attackers will most likely notice the eval() function and monitor them so that they will have a closer look at the data.

On the other hand, there is always an advantage any developer can get when using the eval() function. Aside from ensuring proper functionality of the application, developers can also use the eval() function to provide additional interaction in case the data will not work.

Developers can provide functions or prompts to users that the data used in the application is not acceptable. Without the eval() function, users might never be able to determine that they are working with an application that do not know how to process the data.

But that doesn't mean the functions provided by eval() cannot be replaced. Developers have to remember that there will always be option for additional functions that will replace eval(). A good example is the "if" objects and/or arguments as they will provide the needed option for users.

While they do not have the complete interaction provided by eval() they will still provide the needed data screening before they are used in the JavaScript engine. Other functions would even provide the needed security since they are implemented within the JavaScript engine and browsers.

The eval() function is one of the smartest function developers can use in an Ajax or JavaScript based application. However, there are disadvantages attached to eval() that can place the application in danger. While there are advantages that can be enjoyed using eval(), the disadvantages are too much that it could place the application in jeopardy.

Developers are practically opening their doors to attacks when they use eval(). Fortunately, there are other functions developers can use to replace eval(). Of course, implementing these functions is not as easy compared to eval(). But developers have to spend extra hours in creating codes so that they can develop an efficient and powerful Ajax or JavaScript based application.