c# - Is it better using a guard clause or catching the exception? -

is better prevent exception guard clause or catch exception? there best practice? pro , cons of 2 methodologies?

for example better this:

try {      param=myarray[3]; } catch (indexoutofrangeexception e) {     something... }

or this:

if(myarray.length < 4) {     something... } else {     param=myarray[3]; }

thank answers :)

is better prevent exception guard clause or catch exception?

in case of "boneheaded" exceptions index out of range, former.

in case of "exogenous" exceptions, latter.

pro , cons of 2 methodologies?

there cons of latter in case of boneheaded exceptions. are:

exceptions incredibly expensive compared tests.
exceptions intended model exceptionally rare control flow situations; if potentially accessing index out of range normal don't write exception handler.
exceptions reported "first chance" exceptions listeners even if exception handled. many systems -- asp, example -- listen first chance exceptions, log of them, , treat components produce lot of them buggy, because they are. (i once introduced deliberate first-chance exception in common code path in asp , day later boy did hear it. buggy-subsystem tests went crazy.)
there exceptions call "boneheaded" exceptions -- null dereference, index out of range, , on -- because easy avoid , indicate failures dangerous should always treated fatal bugs , never handled (unless "handler" logging them before shutting down process.) don't handle bug, eliminate bug.

finally, should read article on subject.

Parth Code