I want to get any non empty value from my string array (starting from reverse). I want to use recursive function for achieving my goal. Below is sample of code I have written.
protected string getInvNo(string[] arg, int lengthV)
{
if (arg[lengthV] != "")
return arg[lengthV];
else if (lengthV >= 0)
getInvNo(arg, lengthV-1);
else
return "";
}
It's showing error not all path return value. Requested to help me what's I am missing. Thanks.
I suggest a bit redesign your code:
return in the getInvNo(arg, lengthV-1);null? If we have to skip it as well as empty "" one, string.IsNullOrEmpty is the choiceprotected one I can inherit your class and call the method with any arguments I like)staticImplementation:
// static: you don't use "this" in the context, and the method is not a virtual one
protected static string getInvNo(string[] arg, int index)
{
// Validation
if (null == arg)
throw new ArgumentNullException("arg");
else if (index >= arg.Length)
index = arg.Length - 1; // or throw ArgumentOutOfRangeException("index");
// Stop conditions:
if (index < 0) // 1. Array exhausted
return "";
else if (!string.IsNullOrEmpty(arg[index])) // 2. We've found non-empty value
return arg[index];
return getInvNo(arg, index - 1);
}
Please, notice that usually we solve such problems without recoursion:
using System.Linq;
...
string result = arg.LastOrDefault(item => !string.IsNullOrEmpty(item)) ?? "";
lengthV > 0 will fix the index going out of range to -1.
static string getInvNo(string[] arg, int lengthV)
{
if (arg[lengthV] != "")
{
return arg[lengthV];
}
return lengthV > 0 ? getInvNo(arg, lengthV - 1) : "";
}
Return here:
if (arg[lengthV] != "")
return arg[lengthV];
else if (lengthV >= 0)
getInvNo(arg, lengthV-1);
return "this is your missing return value";
else
return "";
getInvNo(arg, lengthV-1);toreturn getInvNo(arg, lengthV-1);