NPOI XWPF how can I place text on a single line that is both left & right justified? - npoi

Question

I'm new to using NPOI XWPF and trying to create my first document, so far it's going well. The only issue I have left is trying to place text on the same line that is both left and right justified, I want it to look like:
Area: 1(Left Jstfd) Grade Level/Course: 10th Grade Reading (Right Jstfd)
Below is the code snippet I'm using, it's just pushing all the text together on the left side of the page...blah
XWPFParagraph p2 = doc.CreateParagraph();
p2.Alignment = ParagraphAlignment.LEFT;
XWPFRun r3 = p2.CreateRun();
r3.SetBold(true);
r3.FontFamily = "Times New Roman";
r3.FontSize = 12;
r3.SetText("Area: " + ah.schoolArea);
XWPFRun r4 = p2.CreateRun();
r4.SetBold(true);
r4.FontFamily = "Times New Roman";
r4.FontSize = 12;
r4.SetText("Grade Level/Course: " + ah.filterParm);

Answer 1

Before trying to accomplish a task in (N)POI, it's always good to realize how said task is accomplished in Microsoft Word itself. You can't simply split a paragraph half-way a line, what you do is
Add a tab stop at the end of the line
Set it to right-aligned.
Type text on the left, hit tab, type text on the right
Unfortunately, it doesn't seem XWPFParagraph exposes tabstop functionality at this point. However, XWPFParagraph is a wrapper around the CT_P class, which maps 1:1 onto the underlying Office XML format. Using reflection, we can access this private field and use it to directly add the tabstop.
Sample code:
var paragraph = document.CreateParagraph();
var memberInfo = typeof(XWPFParagraph).GetField("paragraph", BindingFlags.NonPublic | BindingFlags.Instance);
if (memberInfo == null)
{
throw new Exception("Could not retrieve CT_P from XWPFParagraph");
}
var internalParagraph = (CT_P) memberInfo.GetValue(paragraph);
CT_PPr pPr = internalParagraph.AddNewPPr();
CT_Tabs tabs = pPr.AddNewTabs();
CT_TabStop tab = tabs.AddNewTab();
tab.pos = "9000";
tab.val = ST_TabJc.right;
var run = paragraph.CreateRun();
run.SetText("Left aligned");
run.AddTab();
run = paragraph.CreateRun();
run.SetText("Right aligned");
Result: