Check if key exists or not in a JavaScript array
Since I work with PHP as well as JavaScript, I know that there is no easy in-built function in JS to check if a given key exists or not in a JavaScript array object. Google-ing for the same returned some user-made functions that were either too long and complicated or even impractical with huge arrays.
The below small snippet works just fine:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | <script type="text/javascript"> //lets setup a sample array and its key-and-values var array=new Array(); array['name']='Rohan Shenoy'; array['gender']='Male'; array['age']='21'; //lets try to find an key which exists if(array['name']==undefined) {alert('That key is undefined');} else {alert('That keys exists');} //lets try to find an key which does NOT exist if(array['residence']==undefined) {alert('That key is undefined');} else {alert('That keys exists');} </script> |
As simple as that!