Category Archives: Knowledge Base

Knowledge Base, WordWriter

How to use merge documents together with Document.Append

Problem

Prior to WordWriter 4.5.0, the only way to merge entire documents was to use InsertAfter. Starting in WordWriter 4.5.0, Document.Append() was introduced as an improved way to merge documents together.

This post covers the behavior of Document.Append().

Solution

The default behavior of Document.Append() is creating a section-page break between the original document and the inserted document:

 documentOne.Append(newDocument);

To merge the two documents so they appear continuous, simply change the section break type to be continuous:

int mySectionsCount = thisDocument.Sections.Length;
thisDocument.Append(otherDocument);
thisDocument.Sections[mySectionsCount].Break = Section.BreakType.Continuous;

Example:

For a more complicated example, here we want to insert into our current work document (thisDocument) a header from one template document and body content from another template document. Note that we want both the header and the body to be on the same page, so we change the type of the section break at the tail of the header to continuous.

// adding header document
Document headerDocument = Wapp.Open(_headerSource);
thisDocument.Append(headerDocument);

// adding body document
Document bodyDocument = Wapp.Open(_bodySource);
int sectionCount = thisDocument.Sections.Length;
thisDocument.Append(bodyDocument);
thisDocument.Sections[sectionCount].Break = Section.BreakType.Continuous;
Note that if the initial document (the one you append into) is empty, we get a blank page at the beginning of the document. To fix that we need to delete the first empty section:

 thisDocument.Sections[0].DeleteElement();

All other InsertAfter operations that don’t deal with sections should stay unchanged.

Knowledge Base, WordWriter

Inserting a subreport into a WordWriter report

Problem

You need to insert a subreport into a larger report using WordWriter.

Solution

Option 1:

Generate each subreport separately and then use the WordApplication API to merge the subreports into the larger report. The subreports could be appended to the main report document with Document.Append, or if you need to insert the subreport into a particular place, you can use Element.InsertAfter or Element.InsertBefore.

Option 2

Flatten your data set and use WordWriter Grouping and Nesting. Grouping and Nesting would allow you repeat sections of a document for a particular subgroup in the data.

NOTE: Both these solutions require WordWriter Enterprise Edition. For more information about the features offered in Enterprise Edition, check out the OfficeWriter Change Log page.

ExcelWriter, Knowledge Base

How to create a chart with different chart types

Problem

ExcelWriter supports creating custom charts, including charts that contain several different chart types. For example, a chart wtih two area series and one line series.

Solution

This code snippet creates a chart with two area series and one line series:

Chart chart = ws.Charts.CreateChart(ChartType.Area.StandardArea,ws.CreateAnchor(5, 0, 0, 0));
chart.SeriesCollection.CreateSeries("A1:A3");
chart.SeriesCollection.CreateSeries("B1:B3", ChartType.Area.StandardArea, AxisType.Primary);
chart.SeriesCollection.CreateSeries("C1:C3", ChartType.Line.StandardLine, AxisType.Primary);

ExcelWriter, Knowledge Base

Optimizing ExcelApplication performance to reduce memory or time usage

Problem

Your program, which uses the ExcelApplication object, is using more memory than you would like or is taking too long to generate a report.

Solution

The Best Pratices with Large Reports article in our documentation discusses how to optimize for large ExcelApplication reports by reducing memory or run time. It includes, but is not limited to:

  • What to avoid when referencing cells, inserting rows or columns, and applying styles
  • Certain methods are known to be memory intensive, such as AutoFitWidth
  • Ways to improve performance by changing how and when data is imported

There are also code examples that compare inefficient code and code that was improved by the recommendations in the article. These code examples are split up into Memory Related Performance Issues and Time Related Performance Issues.

Knowledge Base, WordWriter

Tools to convert Word documents to PDF

Problem

WordWriter does not support converting between file formats. This includes converting between DOC/DOCX and PDF. We generally recommend that you use a 3rd party component to convert Word documents to PDF files.

Solution

Note: Most Word to PDF converters require Office to be installed on the server in order to render the Word components before generating the PDF file. Microsoft does not recommend this:

Microsoft does not currently recommend, and does not support, Automation of Microsoft Office applications from any unattended, non-interactive client application or component (including ASP, ASP.NET, DCOM, and NT Services), because Office may exhibit unstable behavior and/or deadlock when Office is run in this environment.

For more details, see Considerations for server-side Automation of Office.

Word Services for SharePoint

If you are using SharePoint Server 2010, then one possibility is to use Word Services to perform the format conversion. This entails writing code to convert a Word document that is in a list or a document library in SharePoint.

This is a blog post that describes Converting Word Documents to PDF using SharePoint Server 2010 and Word Services. In this case, Word Services automatically converts a document to PDF when the Word document is added to a list.

Rainbow PDF

Rainbow PDF by Atenna House has a server-based converter that does not require Office on the server. However, since Office is not installed, this component does not have the ability to render all Word document elements. Word documents rendered to PDF with Rainbow PDF experience loss of fidelity.

EasyPDF

EasyPDF by BCL Technologies has a a PDF Creator SDK as well as server-side solutions that can convert Word documents to PDF. EasyPDF does require Office to be installed on the server, however it carefully manages the instances of Word to avoid hitting the pitfalls that normally happen when automating Office on the server.

Knowledge Base, WordWriter

How to use merge fields with a bar code format

Problem

You create a Word document containing a merge field formatted with a Bar Code font, such as Code 39. You use the WordTemplate class to process the document. However, in the generated document, the merge field is populated with text in the Times New Roman font. The problem is illustrated in the figures below:

Merge field
Formatted merge field
Output

Solution

A bar code field must begin and end with a delimiter character. For the Code 39 font, this required delimiter is represented in human-readable text as the * character.

When you create the merge field in a Word document, insert the * character into the merge field using merge field switches. Then you can format the merge field with a bar code font. The procedure is as follows:

1. From the Word menu, select Insert, Field.

2. In the dialog box, select MergeField and fill in the fields as illustrated in the figure below. Use an appropriate name for Field name.

After you close the dialog box, the merge field should appear as follows:

3. Select the entire merge field and format it with a bar code font, such as Code 39.

In the generated document, the merge field should now contain the text in the bar code font. The following figure shows the results for the string *0123456789*.

To see that this does in fact represent the correct string, you can select the text and choose a different, readable font, or copy and paste the text into a text editor.

ExcelWriter, Knowledge Base

How to apply auto filters with ExcelApplication

Details

Auto filters are an Excel feature that can be applied to a column of data that allows users to select what rows of data they want visible for a given area on a worksheet.

The ability to apply auto filters programmatically with ExcelApplication in XLSX and XLSM files was added in OfficeWriter 8.3. This post covers how to add auto filters with the ExcelWriter API.

Solution

  1. Define the Area that the auto filter will be applied to.
  2. Get a handle on the AutoFilter object for the Worksheet that will have the auto filter.
  3. Set the worksheet’s AutoFilter.Area to the area that was defined earlier.

Here is the code:

Area filter_area = ws.PopulatedCells; //Returns a continuous area of all the populated cells
AutoFilter filter = ws.AutoFilter;
filter.Area = filter_area;
Here is the code in a single line:
ws.AutoFilter.Area = ws.CreateArea("A1:H1");

Additional Resources

To remove the auto filter from a worksheet, use AutoFilter.Clear():
ws.AutoFilter.Clear();
A few things to bear in mind:

  • A worksheet can only contain one area with auto filters. If you set Worksheet.AutoFilter.Area, you will overwrite any existing auto filters.
  • You must specify the entire area that you want to apply the filters to. ExcelWriter will not automatically detect blank rows and columns. We recommend Worksheet.PopulatedCells for getting a handle on all the populated cells in a worksheet.

ExcelWriter, Knowledge Base

How to use ASP.NET MVC with OfficeWriter

Problem

A number of customers have asked about support for ASP.NET MVC. With the introduction of ASP.NET MVC, the method to send OfficeWriter-generated files to the user requires a few more lines of code. In ASP.NET WebForms, OfficeWriter can write directly to the HttpResponse stream via the Save method, allowing for a one-line implementation. In MVC, all the functions from a Controller return an ActionResult, and it requires a different approach to return the file to the user.

Solution

To facilitate file downloads, we need an ActionResult to return the file generated by OfficeWriter. For use in ASP.NET MVC, we need to return our file via an ActionResult for the Controller’s action; the specific type used below for doing that is the FileStreamResult by using OfficeWriter to get a stream of the file.

The overview of what we need to do is summarized in the algorithm below:

  1. Create the appropriate OfficeWriter object.
  2. Get the data into the file, using the various data binding methods like ExcelTemplate.BindData and WordTemplate.SetDataSource.
  3. Process the file.
  4. Save the file to an in-memory Stream (using MemoryStream); check out ExcelTemplate.Save, ExcelApplication.Save, WordTemplate.Save, and WordApplication.Save.
  5. Return the FileStreamResult, set to use the in-memory Stream.

The following is a C# sample that uses ExcelTemplate. This general approach also works for ExcelApplication, WordTemplate, and WordApplication.

public ActionResult Download()
{
if (ModelState.IsValid)
{
var excelTemplate = new ExcelTemplate();
excelTemplate.Open(Server.MapPath("~/Templates/Download_Template.xlsx"));

// get the data into the file
excelTemplate.Process();
var stream = new MemoryStream();
excelTemplate.Save(stream);

// make sure to reset the position because we will be reading it again
stream.Position = 0;
var actionResult = new FileStreamResult( stream, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" );
actionResult.FileDownloadName = "Download.xlsx"; return actionResult;
} return View();
}
The above code would be placed inside a Controller for the Download action. When this action is activated, a file download prompt will appear for the user with the file name that was given to the FileStreamResult.

ExcelWriter, Knowledge Base

How to create a dual axis chart from bar charts

Problem

With the ExcelApplication object, it is possible to create and manipulate charts, including bar charts with series on both the primary and secondary axes. In this example, we will cover how to use OfficeWriter to create a dual axis bar chart.

Note: The ExcelApplication object is only available in OfficeWriter Enterprise Edition (EE).

Solution

This example assumes that you are familiar with creating charts with ExcelApplication. If you’re not, we recommend that you check out Charts in ExcelApplication.

Let’s start with given data in worksheet Sheet1:

The following code snippet creates a bar chart with two series from that data:

Worksheet wkst = wb.Worksheets["Sheet1"];
Anchor anchr = wkst.CreateAnchor(5, 5, 0, 0);

//Create the chart
Chart chrt = wkst.Charts.CreateChart(ChartType.Bar.Clustered, anchr);

//Set the category axis data for the chart
chrt.SeriesCollection.CategoryData = "A2:A4";

//Create a cluster bar series on the primary axis
Series series1 = chrt.SeriesCollection.CreateSeries("B2:B4", ChartType.Bar.Clustered, AxisType.Primary);

//Create a cluster bar series on the secondary axis
Series series2 = chrt.SeriesCollection.CreateSeries("C2:C4", ChartType.Bar.Clustered, AxisType.Secondary);

If you are working with an existing chart, you can set the Series.AxisType property to AxisType.Secondary.

 series2.AxisType = AxisType.Secondary 
This will produce a chart that looks like the following:

The reason why only one series appears on the chart is because of an issue with how Excel displays bar and column charts on two axes.

To get around this, you should pad your data with zeroed values which act as placeholders for the bar or column chart series. Peltier Tech has a blog post with details on how to show a Column Chart on Two Axes. These principles also apply to bar charts.

This workaround can also be applied to OfficeWriter charts.

Dual Axis Chart Workaround

1. Pad the data to include the zeroed columns.

2. Add code for the place holder series on the primary and secondary axes


//Create a cluster bar series on the primary axis
Series series1 = chrt.SeriesCollection.CreateSeries("B2:B4", ChartType.Bar.Clustered, AxisType.Primary);

//Create the zeroed placeholder series for the primary axis
Series series2_pad = chrt.SeriesCollection.CreateSeries("C2:C4", ChartType.Bar.Clustered, AxisType.Primary);

//Create the zeroed placeholder series for the secondary axis
Series series1_pad = chrt.SeriesCollection.CreateSeries("D2:D4", ChartType.Bar.Clustered, AxisType.Secondary);

//Create a cluster bar series on the secondary axis
Series series2 = chrt.SeriesCollection.CreateSeries("E2:E4", ChartType.Bar.Clustered, AxisType.Secondary);
3. Add code to hide the legend entries for the placeholder series:
//Hide the placeholder legend entries
series2_pad.ShowLegendEntry = false;
series1_pad.ShowLegendEntry = false;
The final chart should display both series correctly on the separate axes:

Note: The change in color is because there are technically 4 series in the chart and Excel’s automatic coloring reflects this.

ExcelWriter, Knowledge Base

How to format alternating color rows with ExcelApplication

Problem

A common way to display data in Excel is to alternate the background color of every other row when displaying a large table of data. With ExcelWriter there are multiple ways to accomplish this. This post covers some possible ways to apply alternating row colors with ExcelApplication.

There is another post that discusses how to do this with ExcelTemplate.

Solution

In versions of ExcelApplication prior to 6.5.1, the only way to set alternating background colors on a table was to loop over all the rows you wanted to format and set their background colors one at a time. This can take a long time for large amounts of data, and requires quite a bit of code. With the introduction of the ConditionalFormat object in ExcelWriter 6.5.1, alternating row colors in a Range with the ExcelApplication object is much simpler and faster.

The first step is to choose colors for the odd and even rows. In this example I’ll color even-numbered rows a light blue and odd-numbered rows white. You can use any colors you like, as long as they exist in the Palette or you add them yourself.

The second step is to create the ConditionalFormat object and the conditions within it. Each Condition has a comparison rule that gets set up in the constructor and a Style object that will be applied to each cell for which that rule is true. To alternate row colors we need two Conditions: one that will format the odd-numbered rows and one for the even-numbered rows.

To do this we use the FormulaEvaluation comparison type and create formulas that evaluate to true depending on the numbering of the row. The MOD() function returns the remainder left after dividing its first argument by its second, and the ROW() function returns the 1-indexed number of the current cell’s row. Thus, MOD(ROW(), 2)=1 will be true for all odd-numbered cells, and MOD(ROW(), 2)=0 will be true for odd-numbered cells.

After creating the conditions, we change the formatting of the Style objects associated with them. For this example all we’ll do is change the background color, but we could apply any formatting that can be set with through the Style object. As in the example below, we suggest that you modify the existing Condition.Style object rather than creating a new Style object and setting Condition.Style to it, as some attributes are not preserved properly with the second method.

The final step is to create the Range this formatting should be applied to and associate the ConditionalFormat with the Range. The following code illustrates these steps and produces the screenshot below.


// Create the colors we'll use on alternating rows. In Excel you can only
// use colors in the Palette, so we need to create a Palette object and use
// that to get the colors.
Palette p = wb.Palette;
Color evenColor = p.GetClosestColor(153, 204, 255);
Color oddColor = p.GetClosestColor(255, 255, 255);

// Create the conditional format and its conditions. Each condition
// has a formula that can evaluate to true or false.
ConditionalFormat oddEvenColors = wb.CreateConditionalFormat();
Condition evenRows;
evenRows = oddEvenColors.CreateCondition(Condition.Comparison.FormulaEvaluation, "=MOD(ROW(), 2)=0");
Condition oddRows; oddRows = oddEvenColors.CreateCondition(Condition.Comparison.FormulaEvaluation, "=MOD(ROW(), 2)=1");

// Change the background color for each condition. This is what will change
// for the cells where the condition is true.
evenRows.Style.BackgroundColor = evenColor;
oddRows.Style.BackgroundColor = oddColor;

// Create the range we want to format and set the formatting.
Range toFormat = ws.CreateRange("A1:F10");
toFormat.SetConditionalFormat(oddEvenColors);

Note that the conditional formatting is applied rather than set. This means that only the differences between any existing styles and the conditional formatting will take effect. For example, if some of the cells in the range had a border or had changed the font size, those changes will not be affected when we change the background color. See our documentation for more on setting and applying styles.