Checking if an array key exists in a JavaScript object or array
For the sake of completeness, you can use the in operator. This is probably the best way to check for missing keys.
1 2 3 4 5 6 7 8 | var hi = {hello: "world"};alert( hi["hello"] ); // popup box with "world"alert( hi["goodbye"] ); // popup boc with "undefined"// this works even if you have {"goodbye": undefined}if( "goodbye" in hi ) { // do something} |
What do you think?