Console assert()
Examples
Write a message to the console:
console.assert(x + y == 11, "Expression returned false");
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Write an object to the console:
const myObj = {firstname:"John", lastname:"Doe"};
console.assert(x + y == 11, myObj);
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More examples below.
Definition and Usage
The assert() method writes a message to the console
if an expression evaluates to false.
Syntax
console.assert(expression, message)
Parameters
| Parameter | Description |
| expression | Required. Any expression. If the expression evaluates to false, a message
is written in the console. |
| message | Required. The message to write in the console. |
More Examples
Check for an element:
console.assert(document.getElementById("demo"), "You have no element with ID 'demo'");
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Write an array to the console:
const myArr = ["Orange", "Banana", "Mango", "Kiwi" ];
console.assert(x + y = 11, myArr);
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Browser Support
console.assert() is supported in all browsers:
| Chrome | IE | Edge | Firefox | Safari | Opera |
| Yes | Yes | Yes | Yes | Yes | Yes |
