Alert command assumes this structure: alert (variable)
No, alert()
assumes this structure:
alert(some expression)
...where "some expression" is pretty much any JavaScript expression - if the expression is not a string it will be converted (though in some cases, e.g., for some objects the result might not be very meaningful).
So:
alert(variable);
alert("string literal");
alert(variable1 + variable2 + variable3);
alert(variable1 + ", " + variable2);
alert(resultOfFunctionCall());
alert([1,2,3]);
alert(whatever() + "else" + you.can.think + "of");
Or even:
alert(); // displays "undefined"
Note that if you are trying to debug your code you are better off using console.log()
than alert()
. If you are trying to produce a dynamic message to show the user just concatenate variables as needed, e.g.:
alert("Hello there " + name + ". Welcome.");
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