Dear Sir or Madam,
I’m trying to include custom content into a header/footer section into an Aspose.Cells.Worksheet. Unfortunately, if the custom content contains the following character sequences & (ampersand) or &" (ampersand followed by a double quote), the resulting Excel file will not display the content properly and instead display shortened or trimmed versions of the text.
For example:
&WO will be displayed as O
&"someText will yield an empty output
The code I’m using in production is similar to this snippet:
var replacements = new Dictionary() { /* add key-value pairs of the replacements */ };
foreach (Worksheet worksheet in workbook.Worksheets)
{
// 3 blocks of header/footer per worksheet (left, center, right)
for (int i = 0; i < 3; i++)
{
// Custom replacements in header section
var adjustedHeader = CheckReplacements(worksheet.PageSetup.GetHeader(i), replacements);
if (!String.IsNullOrEmpty(adjustedHeader))
worksheet.PageSetup.SetHeader(i, adjustedHeader);
// Custom replacements in footer section
var adjustedFooter = CheckReplacements(worksheet.PageSetup.GetFooter(i), replacements);
if (!String.IsNullOrEmpty(adjustedFooter))
worksheet.PageSetup.SetFooter(i, adjustedFooter);
}
}
Is there any function in Aspose.Cells to escape custom text (i.e. the values of my replacements dictionary) content to avoid this issue - especially for user defined content, that’ll be merged into the header/footer sections?
To include custom content in the header or footer of an Aspose.Cells.Worksheet while avoiding issues with special character sequences like & and &", you can use a method to escape these characters. Unfortunately, there isn’t a built-in function in Aspose.Cells specifically for escaping these sequences, but you can implement a simple replacement strategy in your code.
Here’s a suggested approach to handle the special characters in your replacements dictionary:
Escape the Special Characters: Before setting the header or footer, replace & with && and &" with &&" in your custom content. This way, Aspose.Cells will interpret the double ampersand as a literal ampersand.
Update Your Code: Modify your CheckReplacements method to include this escaping logic.
Here’s an example of how you might implement this:
private string EscapeSpecialCharacters(string input)
{
if (string.IsNullOrEmpty(input))
return input;
// Replace & with && and &" with &&"
return input.Replace("&\"", "&&\"").Replace("&", "&&");
}
// Usage in your existing code
var replacements = new Dictionary<String, String>() { /* add key-value pairs of the replacements */ };
foreach (Worksheet worksheet in workbook.Worksheets)
{
for (int i = 0; i < 3; i++)
{
// Custom replacements in header section
var adjustedHeader = EscapeSpecialCharacters(CheckReplacements(worksheet.PageSetup.GetHeader(i), replacements));
if (!String.IsNullOrEmpty(adjustedHeader))
worksheet.PageSetup.SetHeader(i, adjustedHeader);
// Custom replacements in footer section
var adjustedFooter = EscapeSpecialCharacters(CheckReplacements(worksheet.PageSetup.GetFooter(i), replacements));
if (!String.IsNullOrEmpty(adjustedFooter))
worksheet.PageSetup.SetFooter(i, adjustedFooter);
}
}
By implementing this escaping mechanism, you should be able to include special character sequences in your headers and footers without them being trimmed or displayed incorrectly.
If you have further questions or need additional assistance, feel free to ask!
Unfortunately, the code samples in this document do not handle special characters in the text, that’ll be inserted and thus does not answer my question at all.
@M.Heinz
Would you like to provide the expected excel file? If you can take a screenshot and highlight the requirements, it will be very helpful for us to locate the issue. We will check it soon.
Put ##PLACEHOLDER## in one of the sections of the source excel document.
Analogue to the previous code example, simply replace the ##PLACEHOLDER## string in the header/footer section with any user defined string and write it back into the header/footer section. worksheet.PageSetup.SetFooter(0, worksheet.PageSetup.GetFooter(0).Replace("##PLACEHOLDER##", "<user-defined-input>"))
My expectation would be to have a resulting excel document which displays the user defined string as declared - regardless of any special characters.
If the user specifies an ampersand &, the output should be displayed as such &.
If the user specifies an ampersand followed by a number &10, the output should be displayed as such &10.
If the user specifies an ampersand followed by a letter &W, the output should be displayed as such &W.
If the user specifies an ampersand followed by a double quote &", the output should be displayed as such &".
If the user specifies any other text T, the output should be displayed as such T - without interpreting any command sequences or any similar logic.
For one, &W is no command sequence and as such I don’t see, why this would be replaced at all; but I guess, this is an issue in Excel itself and nothing specific to Aspose.
Other than that, even in your screenshot, &WO is being displayed as O, which is not my expectation; I want the user input be shown as given, i.e. convert whatever the user inputs (&WO) into something, that renders as &WO itself.
As previously mentioned by the bot and your documentation, escaping the & with a second one && would yield this result for the ampersand as a special character. And still the question remains: Are there any other special characters, that need special treatment in order not to mess with the input?
Maybe it’s not clear to you, that I’m referring to our customers when I’m saying “user defined input”. I’m personally not in control of said data and neither are our customers willing to comprehend the concept of command sequences in Excel header/footer sections.
As such I’m reliant on the ability to escape arbitrary input, such that the user gets displayed, what they input - without any interpretation of command sequence.
Hence again my question: Is there any other special character in these header/footer sections, that I would need to escape?
@M.Heinz &
Excel files’ Header/Footer contains a number of formatting codes which starts with “&”.
So please replace “&” with “&&” before setting the header/footer with PageSetup.SetFooter or SetHeader() method if they simple text. But do you want to support the commands as “&P” and “&N”?
BTW please get header and footer command script as the following:
No, as stated previously: I do NOT want to support any commands in this type of replacement. Any text input by the user should be displayed exactly as entered by the user.
That’s why I’m so adament about asking for any other special characters I might need to escape besides the ampersand symbol &. But I guess, there simply is no other special character besides the ampersand &; otherwise one of you would have already caught on to my question.
Additionally I’m not interested in reading any command scripts for any header/footer-sections, as there shouldn’t be any; neither pre nor post text replacement.
And regarding your comment:
In my opinion, &WO and &"someText are “simple text” snippets and as such I would have loved to set those e.g. via SetHeader(0, "&WO"), but I guess, the definition of “simple text” differs in our point of views. As those texts yield a truncated text output, those methods ain’t viable for me without escaping the input strings first.
Thanks for all your help; I’ll simply stick to doubling the &.