@Karthik_Test_account You can achieve this either using form fields:
Document doc = new Document();
DocumentBuilder builder = new DocumentBuilder(doc);
// insert checkbox formfield.
builder.InsertCheckBox("Option1", true, 10);
builder.Writeln("Option 1 (should be checked)");
builder.InsertCheckBox("Option2", false, 10);
builder.Writeln("Option 2 (Unchecked)");
builder.InsertCheckBox("Option3", true, 10);
builder.Writeln("Option 3 (Checked)");
doc.Save(@"C:\Temp\out.docx");
or using structured document tags:
Document doc = new Document();
DocumentBuilder builder = new DocumentBuilder(doc);
// insert checkbox SDT.
StructuredDocumentTag sdt1 = new StructuredDocumentTag(doc, SdtType.Checkbox, MarkupLevel.Inline);
sdt1.Checked = true;
builder.InsertNode(sdt1);
builder.Writeln("Option 1 (should be checked)");
StructuredDocumentTag sdt2 = new StructuredDocumentTag(doc, SdtType.Checkbox, MarkupLevel.Inline);
sdt2.Checked = false;
builder.InsertNode(sdt2);
builder.Writeln("Option 2 (Unchecked)");
StructuredDocumentTag sdt3 = new StructuredDocumentTag(doc, SdtType.Checkbox, MarkupLevel.Inline);
sdt3.Checked = true;
builder.InsertNode(sdt3);
builder.Writeln("Option 3 (Checked)");
doc.Save(@"C:\Temp\out.docx");