交叉引用是指同一文檔中其他地方的相關信息,我們可以創建對任何現有項目（如標題，腳注，書簽，標題和編號段落）的交叉引用,本文將展示如何使用C＃和VB.NET的Spire.Doc創建書簽的交叉引用。

Step 1: 創建一個文檔實例。

Document doc = new Document();
Section section = doc.AddSection();

Step 2: 插入一個書簽。

Paragraph paragraph = section.AddParagraph();
paragraph.AppendBookmarkStart("MyBookmark");
paragraph.AppendText("Text inside a bookmark");
paragraph.AppendBookmarkEnd("MyBookmark");

Step 3: 創建交叉引用字段，并通過書簽名稱將其鏈接到書簽。

Field field = new Field(doc);
field.Type = FieldType.FieldRef;
field.Code = @"REF MyBookmark \p \h";

Step 4: 添加一個段落，并將該字段插入段落。

paragraph = section.AddParagraph();
paragraph.AppendText("For more information, see ");
paragraph.ChildObjects.Add(field);

Step 5: 將FieldSeparator對象插入到段落中，該段落在字段中用作分隔符。

FieldMark fieldSeparator= new FieldMark(doc, FieldMarkType.FieldSeparator);
paragraph.ChildObjects.Add(fieldSeparator);

Step 6: 設置交叉引用字段的顯示文本。

TextRange tr = new TextRange(doc);
tr.Text = "above";
paragraph.ChildObjects.Add(tr);

Step 7: 將FieldEnd對象插入段落，該段落用于標記字段的末尾。

FieldMark fieldEnd = new FieldMark(doc, FieldMarkType.FieldEnd);
paragraph.ChildObjects.Add(fieldEnd);

Step 8: 保存到文件。

doc.SaveToFile("output.docx", FileFormat.Docx2013);

導出：交叉引用顯示為將讀者引用到引用項目的鏈接。

完整代碼：

[C#]

Document doc = new Document();
Section section = doc.AddSection();
//create a bookmark
Paragraph paragraph = section.AddParagraph();
paragraph.AppendBookmarkStart("MyBookmark");
paragraph.AppendText("Text inside a bookmark");
paragraph.AppendBookmarkEnd("MyBookmark");
//insert line breaks
for (int i = 0; i < 4; i++)
{
    paragraph.AppendBreak(BreakType.LineBreak);
}        
//create a cross-reference field, and link it to bookmark                    
Field field = new Field(doc);
field.Type = FieldType.FieldRef;
field.Code = @"REF MyBookmark \p \h";
//insert field to paragraph
paragraph = section.AddParagraph();
paragraph.AppendText("For more information, see ");
paragraph.ChildObjects.Add(field);
//insert FieldSeparator object
FieldMark fieldSeparator = new FieldMark(doc, FieldMarkType.FieldSeparator);
paragraph.ChildObjects.Add(fieldSeparator);
//set display text of the field
TextRange tr = new TextRange(doc);
tr.Text = "above";
paragraph.ChildObjects.Add(tr);
//insert FieldEnd object to mark the end of the field
FieldMark fieldEnd = new FieldMark(doc, FieldMarkType.FieldEnd);
paragraph.ChildObjects.Add(fieldEnd);
//save file
doc.SaveToFile("output.docx", FileFormat.Docx2013);

[VB.NET]

Document doc = New Document()
Dim section As Section = doc.AddSection()
'create a bookmark
Dim paragraph As Paragraph = section.AddParagraph()
paragraph.AppendBookmarkStart("MyBookmark")
paragraph.AppendText("Text inside a bookmark")
paragraph.AppendBookmarkEnd("MyBookmark")
'insert line breaks
Dim i As Integer
For i = 0 To  4- 1  Step i + 1
    paragraph.AppendBreak(BreakType.LineBreak)
Next
'create a cross-reference field, and link it to bookmark                    
Dim field As Field = New Field(doc)
field.Type = FieldType.FieldRef
field.Code = "REF MyBookmark \p \h"
'insert field to paragraph
paragraph = section.AddParagraph()
paragraph.AppendText("For more information, see ")
paragraph.ChildObjects.Add(field)
'insert FieldSeparator object
Dim fieldSeparator As FieldMark = New FieldMark(doc, FieldMarkType.FieldSeparator)
paragraph.ChildObjects.Add(fieldSeparator)
'set display text of the field
Dim tr As TextRange = New TextRange(doc)
tr.Text = "above"
paragraph.ChildObjects.Add(tr)
'insert FieldEnd object to mark the end of the field
Dim fieldEnd As FieldMark = New FieldMark(doc, FieldMarkType.FieldEnd)
paragraph.ChildObjects.Add(fieldEnd)
'save file
doc.SaveToFile("output.docx", FileFormat.Docx2013)