Why Does `setTimeout(GetUsersNumber(), 5000)` Execute Immediately Instead of After 5 Seconds?

Function Calls vs. Function Objects in setTimeout

To avoid overloading the server, a webdeveloper intends to update a page value every 5 seconds using setTimeout(). However, the function within the code appears to be triggered immediately instead of being delayed.

Within the code provided:

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setTimeout(GetUsersNumber(), 50000);

The error lies in the distinction between function calls and function objects in JavaScript. In this case, the parentheses are included after the function name, indicating a function call. To use setTimeout correctly, the function object is required, which is defined without parentheses.

By modifying the code to:

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setTimeout(GetUsersNumber, 5000);

setTimeout will now invoke the GetUsersNumber function object after the specified delay of 5 seconds, ensuring that the page value is updated at the desired interval without overloading the server.

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