Here are a few title options capturing the essence of the article in a question format: * Why Can\'t I Add Properties to a JavaScript String? (Direct and clear) * JavaScript Primitive Type Limitation

Understanding JavaScript Primitive Types and Property Assignment Limitations

Why Can't I Add Properties to a String Primitive?

JavaScript has eight language types: seven primitive types and one non-primitive type (Object). Primitive values (e.g., string, number) are immutable and cannot have properties assigned to them.

When assigning a property to a variable, JavaScript determines the behavior based on the variable's type:

• (a) For undefined or null variables, an error is thrown.
• (b) For Object variables, the property is created or set if already existing.
• (c) For primitive variables (excluding Object), a TypeError is thrown in strict mode or the assignment is ignored in loose mode.

In the provided example, test is a string primitive, so assigning a property to it has no effect:

<code class="js">var test = "test";
test.test = "test inner";
console.log(test); // "test"
console.log(test.test); // undefined</code>

Workarounds for Sorting Dates

Instead of adding properties to strings, consider the following workarounds for sorting dates in the grid:

• Cast Strings to Date Objects: Convert the strings to Date objects before binding to the grid. This requires modifying the code where dates are currently converted to strings.
• Custom Sorting Function: Define a custom sorting function that parses the dates from the strings and performs the sorting based on the parsed Date objects.
• Use a Date-Enabled Grid: Explore alternative grids or libraries that support binding to Date objects directly.
• Accessor Properties (Not Recommended): As mentioned in the response, ES5 introduced accessor properties. However, adding accessor properties to built-in prototypes is not considered best practice.

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