MS Word Mail Merge field format lost when using FieldMergingCallback in aspose word

Question

I have a template that have some merge fields that are in side and out side a table. The values for these fields are query and cached to map then set to the field by a cusstom FieldMergingCallback, here is the java code:

// doc is a Document object
doc.getMailMerge().setFieldMergingCallback(new IFieldMergingCallback() {
    @Override
    public void fieldMerging(FieldMergingArgs arg0) throws Exception {
        if (fieldCache.containsKey(arg0.getFieldName())) {
            arg0.setText(fieldCache.get(arg0.getFieldName()));
        }
   }

   @Override
   public void imageFieldMerging(ImageFieldMergingArgs arg0) throws Exception {
       return;
   }
});

The problem is I lost all field format (\* Caps, \* Upper, etc…) when using setText method, I have tried to call doc.updateFields() after the call to executeWithRegions() but the format still lost.

How can I reserve format in the call back?

This is a legacy system so we are stuck in aspose word 14.5.0

Answer 1

UPDATE 02-2020: Aspose word 20.2 has implemented this feature. https://forum.aspose.com/t/merge-field-format-lost-when-using-fieldmergingcallback/206900/5

According to the replies to the same question of mine on aspose forum, currently there is no support for keeping formatting in FieldMergingCallback. So, I end up with a work around, the idea is in every call back, I create a fake document and clone the current field to this fake document, excute it to get the final result, then set it back to the actual field with setText function:

doc.getMailMerge().setFieldMergingCallback(new IFieldMergingCallback(){
    @Override
    public void fieldMerging(FieldMergingArgs e)throws Exception{
        if(cache.containsKey(e.getFieldName())){
            Document fakeDoc=new Document();
            DocumentBuilder builder=new DocumentBuilder(fakeDoc);
            builder.insertField(e.getField().getFieldCode());
            fakeDoc.getMailMerge().setFieldMergingCallback(new IFieldMergingCallback(){
                @Override
                public void fieldMerging(FieldMergingArgs arg)throws Exception{
                    DocumentBuilder innerBuilder=new DocumentBuilder(arg.getDocument());
                    innerBuilder.moveToMergeField(arg.getFieldName(),false,false);
                    innerBuilder.startBookmark(arg.getFieldName());
                    innerBuilder.moveToMergeField(arg.getFieldName(),true,false);
                    innerBuilder.endBookmark(arg.getFieldName());
                }

                @Override
                public void imageFieldMerging(ImageFieldMergingArgs arg){

                }
            });
            fakeDoc.getMailMerge().execute(new String[]{e.getFieldName()},new Object[]{cache.get(e.getFieldName())});
           // Set the formatted text to the actual field
            e.setText(fakeDoc.getRange().getBookmarks().get(0).getText());
        }
    }

    @Override
    public void imageFieldMerging(ImageFieldMergingArgs args){
    }
});

Answer 2

You can use field code to get switches and format the value accordingly. Please see the following code:

        doc.getMailMerge().setFieldMergingCallback(new IFieldMergingCallback() {
            @Override
            public void fieldMerging(FieldMergingArgs args) throws Exception {

                // This is a dummy value.
                String value = args.getFieldName();
                // Get field code to check formatting switches.
                String fieldCode = args.getField().getFieldCode(false);

                // Format the value according to the switches in the field code.
                if (fieldCode.contains("\\* Upper"))
                    value = value.toUpperCase();
                if (fieldCode.contains("\\* Lower"))
                    value = value.toLowerCase();

                args.setText(value);
            }

            @Override
            public void imageFieldMerging(ImageFieldMergingArgs arg0) throws Exception {
                return;
            }
        });

Hope this helps.

Disclosure: I work at Aspose.Words team.