Index was out of range

mike Delvotti

I'm getting the following message pop up even though the function works:

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name:Index

I think it may be a null issue, but what would be the best way to overcome it on my code below. Basiclly i fill my dataset then databind it to a datagridview, then i hide columns i don't need to be seen in my datagrid, although the datagrid fills fine it throws the above message. my sample code below:

DataSet dsLookup = new DataSet();

dsLookup.ReadXml(response.GetResponseStream());

                            dataGridView1.DataSource = dsLookup.Tables[0];
                            dataGridView1.Columns["StockNumber"].DisplayIndex = 0;
                            dataGridView1.Columns["RegistrationNumber"].DisplayIndex = 1;

                            dataGridView1.Columns[0].Visible = false;
                            dataGridView1.Columns[1].Visible = false;

9 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes14y ago
Accepted answer
In fact here's a better way. Just replace this block of statements:

dataGridView1.Columns[21].Visible = false;
dataGridView1.Columns[22].Visible = false;
dataGridView1.Columns[23].Visible = false;
dataGridView1.Columns[24].Visible = false;
dataGridView1.Columns[25].Visible = false;
dataGridView1.Columns[26].Visible = false;
dataGridView1.Columns[27].Visible = false;
dataGridView1.Columns[28].Visible = false;
dataGridView1.Columns[29].Visible = false;

With this one:

for(int i = 21; i < dataGridView1.Columns.Count; i++) dataGridView1.Columns[i].Visible = false;
0
Vulpes14y ago
Thought I'd just add that, if there's a possibility that the XML file might not contain at least 22 columns, then you'll need to do individual 'if' statements on the earlier lines for which Visible is being set to false.
0
mike Delvotti14y ago
Ooops, you posted while i was typing and answered my question, once again Thanks Vulpes :)
0
mike Delvotti14y ago
Yes, it has - Thanks vulpes.

Can i use that on the other lines as well as a failsafe incase on other returns the lines don't exist either? for instance as below:

if (dataGridView1.Columns.Count > 28)
dataGridView1.Columns[28].Visible = false;
if (dataGridView1.Columns.Count > 29)
dataGridView1.Columns[29].Visible = false;

so if in future say one of the xml returns only come back with 10 coulmns in theory with that code as above on every line it wouldn't matter is that correct?
0
Vulpes14y ago
If you replace this line:

dataGridView1.Columns[29].Visible = false;

with:

if (dataGridView1.Columns.Count > 29) dataGridView1.Columns[29].Visible = false;

then that should fix it.
0
mike Delvotti14y ago
Ah, yes thanks Vulpes you are indeed correct, the fault is thrown on this line:

dataGridView1.Columns[29].Visible = false;

In that case is there any way to check to see if those columns exist? as some returns may contain column[29]
0
Vulpes14y ago
I doubt whether this is to do with whether some of the columns in the DGV are null or not.

A more likely explanation is that the XML file is such that it's not generating 30 columns of data.

If you're not sure, you could try commenting out lines starting from the bottom until a point is reached when the exception no longer occurs.
0
mike Delvotti14y ago
Hi Vulpes, yes sorry there is more code, the complete example is below:

                     I think the below section here maybe throwing the fault as some of the entries it returns are blank and maybe needs to ignore nulls?

                    dataGridView1.Columns["StockNumber"].DisplayIndex = 0;
                    dataGridView1.Columns["RegistrationNumber"].DisplayIndex = 1;
                    dataGridView1.Columns["MakeDescription"].DisplayIndex = 2;
                    dataGridView1.Columns["ModelDescription"].DisplayIndex = 3;
                    dataGridView1.Columns["SpecDescription"].DisplayIndex = 4;
                    dataGridView1.Columns["Colour"].DisplayIndex = 5;
                    dataGridView1.Columns["BodyStyle"].DisplayIndex = 6;
                    dataGridView1.Columns["Transmission"].DisplayIndex = 7;
                    dataGridView1.Columns["EngineSize"].DisplayIndex = 8;
                    dataGridView1.Columns["FuelType"].DisplayIndex = 9;
                    dataGridView1.Columns["Mileage"].DisplayIndex = 10;
                    dataGridView1.Columns["RetailPrice"].DisplayIndex = 11;
                    The section below here is simply to remove unwanted columns from the grid
                    dataGridView1.Columns[0].Visible = false;
                    dataGridView1.Columns[1].Visible = false;
                    dataGridView1.Columns[2].Visible = false;
                    dataGridView1.Columns[3].Visible = false;
                    dataGridView1.Columns[4].Visible = false;
                    dataGridView1.Columns[6].Visible = false;
                    dataGridView1.Columns[9].Visible = false;
                    dataGridView1.Columns[14].Visible = false;
                    dataGridView1.Columns[21].Visible = false;
                    dataGridView1.Columns[22].Visible = false;
                    dataGridView1.Columns[23].Visible = false;
                    dataGridView1.Columns[24].Visible = false;
                    dataGridView1.Columns[25].Visible = false;
                    dataGridView1.Columns[26].Visible = false;
                    dataGridView1.Columns[27].Visible = false;
                    dataGridView1.Columns[28].Visible = false;
                    dataGridView1.Columns[29].Visible = false;
0
Vulpes14y ago
Mike,

I think you'll need to pinpoint the line where the exception is being thrown using the debugger.

My suspicion is that it isn't occurring on any of the lines you've shown.

On the face of it, it could only occur on the last, or last but one, lines. But there must be at least two columns in the table otherwise the code would not have got through the two lines before those so an index of 0 or 1 can't be out of range.
0