Why Does Using a Global Variable Named 'name' in JavaScript Cause Unexpected Behavior?

The Curious Case of "name" in JavaScript Objects

When working with JavaScript objects, one might encounter an unexpected behavior when using a global variable named "name." This variable holds a unique significance in different contexts.

Consider the following code snippet:

var name = {};
name.FirstName = 'Tom';
alert(name.FirstName);
alert(name); // Weird value

In Chrome, alert(name.FirstName) returns undefined, while it works as expected in IE and Firefox. Additionally, alert(name) produces a strange value, raising questions about its behavior.

The cause of this issue lies in the special role of the "name" property in JavaScript's global scope. The window.name property is intended to be a string, representing the name of the current window or frame. When creating a global variable named "name," it implicitly sets window.name to a string, essentially overwriting the special value.

Subsequently, when trying to access name.FirstName, it attempts to retrieve a property from a primitive (string) rather than an object, resulting in undefined. This behavior is specific to Chrome, which enforces the intended purpose of window.name by casting the global "name" variable to a string.

To avoid this issue, refrain from using "name" as a global variable, as it can lead to unexpected outcomes. By avoiding this variable, you can ensure that your code behaves consistently across different browsers.

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