Datatable cell to list & using string list in Legends

Question

I am comparing values in datatable column , I want to store the
string in table7.Rows[yy]["Die_ID"] in to a string array.how to solve this

string[] a = null;
if(table7.Columns.Contains(colx))
{
for (int yy=0; yy<table7.Rows.Count; yy++)
{

double tval = double.Parse(table7.Rows[yy][colx].ToString());

if (tval < lower || tval > upper)
{
a[yy] = table7.Rows[yy]["Die_ID"].ToString();
//Error I want to store the string values in a string array :Object reference not set to an //instance of an object.

}

}

}

Vulpes · Answer

Try this (CORRECTED): LegendItem firstItem = new LegendItem(); Font f = new Font(Georgia 16); foreach(string s in list) { LegendCell firstCell = new LegendCell(LegendCellType.Text Die_ID = _ + s ContentAlignment.BottomCenter); firstCell.Font = f; firstItem.Cells.Add(firstCell); }

Vulpes · Answer

Ah so the trick was to create just one LegendCell object and add all the list elements inclusive of new lines to that. Previously we were adding a new LegendCell object for each element of the list and it may be that you're stuck with a horizontal arrangement if you do that. Good thinking :)

Vulpes · Answer

If you create an array based on the number of rows in table7: a = new string[table7.Rows.Count]; then those elements of this array for which tval >= lower && tval If you're only interested in the non-null values then you could copy them first to a list and then convert it to an array: string[] a = null; if(table7.Columns.Contains(colx)) { List list = new List (); for (int yy=0; yy { double tval = double.Parse(table7.Rows[yy][colx].ToString()); if (tval upper) { list.Add(table7.Rows[yy][Die_ID].ToString()); } } a = list.ToArray(); }

Ranjit Powar · Answer

You should create array object using new keyword before using the array.

Farhan Shariff · Answer

Got it Text has to be added first and then once all the text is inserted Cell has to be added egendItem firstItem = new LegendItem(); Font f = new Font(Serif 14 FontStyle.Bold); LegendCell firstCell = new LegendCell(); for (int l = 0; l { firstCell.Text = list[l] + Environment.NewLine +firstCell.Text; firstCell.Font = f; } firstItem.Cells.Add(firstCell);

Farhan Shariff · Answer

Yeah exactly all thanks to you for firstCell.Text or else it would not have been possible http://imgur.com/UIQxIGH

Vulpes · Answer

If inserting new lines 'manually' is not working then there must be a property which controls whether the LegendCells are arranged horizontally or vertically. I couldn't find anything in the docs for the LegendItem class which is where I'd have expected it to be. However the Legend class has a LegendStyle property which looks promising and I'd try setting this to LegendStyle.Column. The Legend object to be used for this purpose is of course the one to whose CustomItems collection the current LegendItem is being added.

Farhan Shariff · Answer

its not working its the same as before. Instead of having a new line it just added a space. http://imgur.com/ZjPEhhb

Vulpes · Answer

If you mean one after the other vertically  I'd try: int index = 0; foreach(string s in list) { LegendCell firstCell = new LegendCell(LegendCellType.Text Die_ID = _ + s ContentAlignment.BottomCenter); if (index > 0) firstCell.Text = 
 + firstCell.Text; index++; firstCell.Font = f; firstItem.Cells.Add(firstCell); }

Farhan Shariff · Answer

yes works perfect the output little bit of trimming remaining http://i.imgur.com/2lKnOGP.png foreach(string s in list) { LegendCell firstCell = new LegendCell(LegendCellType.Text Die_ID = _ + s ContentAlignment.BottomCenter); firstCell.Font = f; firstItem.Cells.Add(firstCell); } H ow to print these strings one after the other also some string is printed out of chart area I used +
 +
 Environment . NewLine

Vulpes · Answer

Sorry again that's just a typo. Should of course be: firstCell.Font = f; Looking through the docs I can't see another way to add the font. It seems you have to set each cell individually though we're now using the same Font object for them all rather than creating a new object for each cell.

Farhan Shariff · Answer

firstcell.Font = f; //The name 'firstcell' does not exist in the current context is there any other way to add the font LegendItem firstItem = new LegendItem(); Font f = new Font(Georgia 16); foreach (string s in list) { LegendCell firstCell = new LegendCell(LegendCellType.Text Die_ID = _ + s ContentAlignment.BottomCenter); firstcell.Font = f; firstItem.Cells.Add(firstCell); } Legend myLegend = new Legend(MainLegend); myLegend.CustomItems.Add(firstItem); chart1.Legends.Add(myLegend);

Vulpes · Answer

Sorry I seem to have lost a bit of code when pasting that in from Notepad. I've corrected it now :)

Farhan Shariff · Answer

LegendCell firstCell = new LegendCellType.Text Die_ID : + s ContentAlignment.BottomCenter); foreach(string s in list) { LegendCell firstCell = new LegendCellType.Text Die_ID = _ + s ContentAlignment.BottomCenter); /* .Text -System.Windows.Forms.DataVisualization.Charting.LegendCellType.Text' is a 'field' but is used like a 'type' //Only assignment call increment decrement await and new object expressions can be used as a statement*/ ' firstcell.Font = f; //The name 'firstcell' does not exist in the current context firstItem.Cells.Add(firstCell); }

Farhan Shariff · Answer

I think only list will work fine. I want to print this list /string array in legends (chart area) how to do that something like LegendItem firstItem = new LegendItem(); LegendCell firstcell = new LegendCell(LegendCellType.Text Die_ID = _//print the list_foreach (int i in list) {+i.ToString() } ContentAlignment.BottomCenter); firstcell.Font = new Font(Georgia 16);