System.IndexOutOfRangeException for a dynamic initialized array

Question

var objTypeIndex = from u in context.sistema_DocType_Index where u.docTypeId == id select u.indexId;
indexIds = objTypeIndex.ToList();
int count = indexIds.Count();

string[] names = new string[] {};
int i = 0;                    

foreach (int indexId in indexIds)
{
    //resgata nome do indice e armazena em um array
    string strIndiceID = indexId.ToString();
    int indiceID = Convert.ToInt32(strIndiceID);
    var objIndexName = from u in context.sistema_Indexes where u.id == indiceID select u.idName;
    name = 

    names[i] = objIndexName.First();

    i++;
}

This line above the last: names[i] = objIndexName.First();

gives the following error:

System.IndexOutOfRangeException: Index was outside the bounds of the array.

I know what that means.. I just can´t figure out why.

You're initiating string[] names as an empty array, setting int i = 0, then accessing names[i] - which is names[0] - which doesn't exist, since your length is 0, not 1. — zimdanen
– zimdanen, Commented Dec 4, 2012 at 19:24
I've removed the MVC/ASP.NET tags as they're irrelevant to the problem. — Jon Skeet
– Jon Skeet, Commented Dec 4, 2012 at 19:24
Why do you take an integer, convert it to a string, and then parse it right back into an int inside of the foreach loop? Just use indexId instead. — Servy
– Servy, Commented Dec 4, 2012 at 19:31

Jon Skeet · Accepted Answer · 2012-12-04 19:23:44Z

4

Look here:

string[] names = new string[] {};

You've created an empty array. You can't put any element into that array. There is no value of i for which this statement will work:

names[i] = objIndexName.First();

It's not clear what you're trying to do, but perhaps you want a List<string> to build up (with Add) rather than an array? Or you could probably do the whole thing with a single LINQ query...

answered Dec 4, 2012 at 19:23

Jon Skeet

1.5m893 gold badges9.3k silver badges9.3k bronze badges

Sign up to request clarification or add additional context in comments.

Comments

lontivero · Accepted Answer · 2012-12-04 19:27:31Z

3

Replace

string[] names = new string[] {};

By

var names = new List<string>();

And instead of

names[i] = objIndexName.First();

Use

names.Add(objIndexName.First());

Then, you will be able to get your array as follow:

var nameArray = names.ToArray();

answered Dec 4, 2012 at 19:27

lontivero

5,2735 gold badges27 silver badges43 bronze badges

Collectives™ on Stack Overflow

System.IndexOutOfRangeException for a dynamic initialized array

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related