indexing - Error : Index was outside the bounds of the array in c# -

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• system.indexoutofrangeexception: index out of bounds 2 answers

i'm trying write small program using c# interface concept area of circle & square.while giving specific condition if (args[0] == "s") there error indexoutofrangeexception:

if (args[0]=="s")     fig = new square(); if (args[0]=="c")     fig = new circle(); 

that happen if args empty. can't ask first element of empty array, because there isn't one. should check length first:

if (args.length == 0) {     // maybe exit? valid not specify arguments? } // either use "else" here, or if you've quit in "if" block // don't need because know there's @ least // 1 argument