JavaScript Eval | JS Eval | JavaScript Eval Function Tutorial

JavaScript Eval


JavaScript eval()
In this tutorial you will learn about JavaScript eval() Method. The eval() method is JavaScript Global method. The eval() evaluates or executes an argument. The eval() method evaluates JavaScript code represented as a string.
Warning: Executing JavaScript from a string is an enormous security risk. It is far too easy for a bad actor to run arbitrary code when you use eval(). See Never use eval()!, below.
Example1
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Example2
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Parameters
String: A string representing a JavaScript expression, statement, or sequence of statements. The expression can include variables and properties of existing objects.
Never use eval()!
The aval() method is a dangerous method because it executes the code it's passed with the privileges of the caller. If you run eval() with a string that could be affected by a malicious party, you may end up running malicious code on the user's machine with the permissions of your webpage / extension. More importantly, a third-party code can see the scope in which eval() was invoked, which can lead to possible attacks in ways to which the similar Function is not susceptible.