Can someone please tell me how to create a file and make it available for download via browser button?
I have read about FileWriter but not found any proper example how to use it
and I found a post How to use the dart:html library to write html files?
but the answer just refers to html5lib which just answers how to parse a String to HTML but not how to save as a file.
help appreciated. Am I missing something or there is no example for that usecase??
Personally, I use a combination of Blob, Url.createObjectUrlFromBlob And AnchorElement (with download and href properties) to create a downloadable file.
Very simple example:
// Assuming your HTML has an empty anchor with ID 'myLink'
var link = querySelector('a#myLink') as AnchorElement;
var myData = [ "Line 1\n", "Line 2\n", "Line 3\n"];
// Plain text type, 'native' line endings
var blob = new Blob(myData, 'text/plain', 'native');
link.download = "file-name-to-save.txt";
link.href = Url.createObjectUrlFromBlob(blob).toString();
link.text = "Download Now!";
As alluded to by Günter Zöchbauer's comment, an alternative to using Blobs is to base64-encode the data and generate a data URL yourself (at least for file sizes that are well within the data URL limits of most browsers). For example:
import 'dart:html';
Uint8List generateFileContents() { ... }
void main() {
var bytes = generateFileContents();
(querySelector('#download-link') as AnchorElement)
..text = 'Download File'
..href = UriData.fromBytes(bytes).toString()
..download = 'filename';
}
Also note that if you do want to use a Blob and want to write binary data from a Uint8List, you are expected to use Blob([bytes], ...) and not Blob(bytes, ...). For example:
var bytes = generateFileContents();
var blob = Blob([bytes], 'application/octet-stream');
(querySelector('#download-link') as AnchorElement)
..text = 'Download File'
..href = Url.createObjectUrlFromBlob(blob)
..download = 'filename';
Related
I'm getting same error as this question, but with XQuery:
SaxonApiException: The context item for axis step ./CLIENT is absent
When running from the command line, all is good. So I don't think there is a syntax problem with the XQuery itself. I won't post the input file unless needed.
The XQuery is displayed with a Console.WriteLine before the error appears:
----- Start: XQUERY:
(: FLWOR = For Let Where Order-by Return :)
<MyFlightLegs>
{
for $flightLeg in //FlightLeg
where $flightLeg/DepartureAirport = 'OKC' or $flightLeg/ArrivalAirport = 'OKC'
order by $flightLeg/ArrivalDate[1] descending
return $flightLeg
}
</MyFlightLegs>
----- End : XQUERY:
Error evaluating (<MyFlightLegs {for $flightLeg in root/descendant::FlightLeg[DepartureAirport = "OKC" or ArrivalAirport = "OKC"] ... return $flightLeg}/>) on line 4 column 20
XPDY0002: The context item for axis step root/descendant::FlightLeg is absent
I think that like the other question, maybe my input XML file is not properly specified.
I took the samples/cs/ExamplesHE.cs run method of the XQuerytoStream class.
Code there for easy reference is:
public class XQueryToStream : Example
{
public override string testName
{
get { return "XQueryToStream"; }
}
public override void run(Uri samplesDir)
{
Processor processor = new Processor();
XQueryCompiler compiler = processor.NewXQueryCompiler();
compiler.BaseUri = samplesDir.ToString();
compiler.DeclareNamespace("saxon", "http://saxon.sf.net/");
XQueryExecutable exp = compiler.Compile("<saxon:example>{static-base-uri()}</saxon:example>");
XQueryEvaluator eval = exp.Load();
Serializer qout = processor.NewSerializer();
qout.SetOutputProperty(Serializer.METHOD, "xml");
qout.SetOutputProperty(Serializer.INDENT, "yes");
qout.SetOutputStream(new FileStream("testoutput.xml", FileMode.Create, FileAccess.Write));
Console.WriteLine("Output written to testoutput.xml");
eval.Run(qout);
}
}
I changed to pass the Xquery file name, the xml file name, and the output file name, and tried to make a static method out of it. (Had success doing the same with the XSLT processor.)
static void DemoXQuery(string xmlInputFilename, string xqueryInputFilename, string outFilename)
{
// Create a Processor instance.
Processor processor = new Processor();
// Load the source document
DocumentBuilder loader = processor.NewDocumentBuilder();
loader.BaseUri = new Uri(xmlInputFilename);
XdmNode indoc = loader.Build(loader.BaseUri);
XQueryCompiler compiler = processor.NewXQueryCompiler();
//BaseUri is inconsistent with Transform= Processor?
//compiler.BaseUri = new Uri(xqueryInputFilename);
//compiler.DeclareNamespace("saxon", "http://saxon.sf.net/");
string xqueryFileContents = File.ReadAllText(xqueryInputFilename);
Console.WriteLine("----- Start: XQUERY:");
Console.WriteLine(xqueryFileContents);
Console.WriteLine("----- End : XQUERY:");
XQueryExecutable exp = compiler.Compile(xqueryFileContents);
XQueryEvaluator eval = exp.Load();
Serializer qout = processor.NewSerializer();
qout.SetOutputProperty(Serializer.METHOD, "xml");
qout.SetOutputProperty(Serializer.INDENT, "yes");
qout.SetOutputStream(new FileStream(outFilename,
FileMode.Create, FileAccess.Write));
eval.Run(qout);
}
Also two questions regarding "BaseURI".
1. Should it be a directory name, or can it be same as the Xquery file name?
2. I get this compile error: "Cannot implicity convert to "System.Uri" to "String".
compiler.BaseUri = new Uri(xqueryInputFilename);
It's exactly the same thing I did for XSLT which worked. But it looks like BaseUri is a string for XQuery, but a real Uri object for XSLT? Any reason for the difference?
You seem to be asking a whole series of separate questions, which are hard to disentangle.
Your C# code appears to be compiling the query
<saxon:example>{static-base-uri()}</saxon:example>
which bears no relationship to the XQuery code you supplied that involves MyFlightLegs.
The MyFlightLegs query uses //FlightLeg and is clearly designed to run against a source document containing a FlightLeg element, but your C# code makes no attempt to supply such a document. You need to add an eval.ContextItem = value statement.
Your second C# fragment creates an input document in the line
XdmNode indoc = loader.Build(loader.BaseUri);
but it doesn't supply it to the query evaluator.
A base URI can be either a directory or a file; resolving relative.xml against file:///my/dir/ gives exactly the same result as resolving it against file:///my/dir/query.xq. By convention, though, the static base URI of the query is the URI of the resource (eg file) containing the source query text.
Yes, there's a lot of inconsistency in the use of strings versus URI objects in the API design. (There's also inconsistency about the spelling of BaseURI versus BaseUri.) Sorry about that; you're just going to have to live with it.
Bottom line solution based on Michael Kay's response; I added this line of code after doing the exp.Load():
eval.ContextItem = indoc;
The indoc object created earlier is what relates to the XML input file to be processed by the XQuery.
I encountered a problem with setting the page header text containing ampersand like ‘a&b’. The text after ‘&’ disappears in the pdf maybe because it is the reserved key in Aspose. My code looks like this:
PageSetup pageSetup = workbook.getWorksheets().get(worksheetName).getPageSetup();
//calling the function
setHeaderFooter(pageSetup, parameters, criteria)
//function for setting header and footer
def setHeaderFooter(PageSetup pageSetup, parameters, criteria = [:])
{
def selectedLoa=getSelectedLoa(parameters)
if(selectedLoa.length()>110){
String firstLine = selectedLoa.substring(0,110);
String secondLine = selectedLoa.substring(110);
if(secondLine.length()>120){
secondLine = secondLine.substring(0,122)+"...."
}
selectedLoa = firstLine+"\n"+secondLine.trim();
}
def periodInfo=getPeriodInfo(parameters, criteria)
def reportingInfo=periodInfo[0]
def comparisonInfo=periodInfo[1]
def benchmarkName=getBenchmark(parameters)
def isNonComparison = criteria.isNonComparison?
criteria.isNonComparison:false
def footerInfo="&BReporting Period:&B " + reportingInfo+"\n"
if (comparisonInfo && !isNonComparison){
footerInfo=footerInfo+"&BComparison Period:&B " +comparisonInfo+"\n"
}
if (benchmarkName){
footerInfo+="&BBenchmark:&B "+benchmarkName
}
//where I encounterd the issue,selectedLoa contains string with ampersand
pageSetup.setHeader(0, pageSetup.getHeader(0) + "\n&\"Lucida Sans,Regular\"&8&K02-074&BPopulation:&B "+selectedLoa)
//Insertion of footer
pageSetup.setFooter(0,"&\"Lucida Sans,Regular\"&8&K02-074"+footerInfo)
def downloadDate = new Date().format("MMMM dd, yyyy")
pageSetup.setFooter(2,"&\"Lucida Sans,Regular\"&8&K02-074" + downloadDate)
//Insertion of logo
try{
def bucketName = parameters.containsKey('printedRLBucketName')?parameters.get('printedRLBucketName'):null
def filePath = parameters.containsKey('printedReportLogo')?parameters.get('printedReportLogo'): null
// Declaring a byte array
byte[] binaryData
if(!filePath || filePath.contains("null") || filePath.endsWith("null")){
filePath = root+"/images/defaultExportLogo.png"
InputStream is = new FileInputStream(new File(filePath))
binaryData = is.getBytes()
}else {
AmazonS3Client s3client = amazonClientService.getAmazonS3Client()
S3Object object = s3client.getObject(bucketName, filePath)
// Getting the bytes out of input stream of S3 object
binaryData = object.getObjectContent().getBytes()
}
// Setting the logo/picture in the right section (2) of the page header
pageSetup.setHeaderPicture(2, binaryData);
// Setting the script for the logo/picture
pageSetup.setHeader(2, "&G");
// Scaling the picture to correct size
Picture pic = pageSetup.getPicture(true, 2);
pic.setLockAspectRatio(true)
pic.setRelativeToOriginalPictureSize(true)
pic.setHeight(35)
pic.setWidth(Math.abs(pic.getWidth() * (pic.getHeightScale() / 100)).intValue());
}catch (Exception e){
e.printStackTrace()
}
}
In this case, I get only ‘a’ in the pdf header all other text after ampersand gets disappeared. Please suggest me with a solution for this. I am using aspose 18.2
We have added header on a PDF page with below code snippet but we did not notice any problem when ampersand sign is included in header text.
// open document
Document document = new Document(dataDir + "input.pdf");
// create text stamp
TextStamp textStamp = new TextStamp("a&bcdefg");
// set properties of the stamp
textStamp.setTopMargin(10);
textStamp.setHorizontalAlignment(HorizontalAlignment.Center);
textStamp.setVerticalAlignment(VerticalAlignment.Top);
// set text properties
textStamp.getTextState().setFont(new FontRepository().findFont("Arial"));
textStamp.getTextState().setFontSize(14.0F);
textStamp.getTextState().setFontStyle(FontStyles.Bold);
textStamp.getTextState().setFontStyle(FontStyles.Italic);
textStamp.getTextState().setForegroundColor(Color.getGreen());
// iterate through all pages of PDF file
for (int Page_counter = 1; Page_counter <= document.getPages().size(); Page_counter++) {
// add stamp to all pages of PDF file
document.getPages().get_Item(Page_counter).addStamp(textStamp);
}
// save output document
document.save(dataDir + "TextStamp_18.8.pdf");
Please ensure using Aspose.PDF for Java 18.8 in your environment. For further information on adding page header, you may visit Add Text Stamp in the Header or Footer section.
In case you face any problem while adding header, then please share your code snippet and generated PDF document with us via Google Drive, Dropbox etc. so that we may investigate it to help you out.
PS: I work with Aspose as Developer Evangelist.
Well, yes, "&" is a reserved word when inserting headers/footers in MS Excel spreadsheet via Aspose.Cells APIs. To cope with your issue, you got to place another ampersand to paste the "& (ampersand)" in the header string. See the sample code for your reference:
e.g
Sample code:
Workbook wb = new Workbook();
Worksheet ws = wb.getWorksheets().get(0);
ws.getCells().get("A1").putValue("testin..");
String headerText="a&&bcdefg";
PageSetup pageSetup = ws.getPageSetup();
pageSetup.setHeader(0, headerText);
wb.save("f:\\files\\out1.xlsx");
wb.save("f:\\files\\out2.pdf");
Hope this helps a bit.
I am working as Support developer/ Evangelist at Aspose.
As per in this FileHelpers 3.1 example, you can automatically detect a CSV file format using the FileHelpers.Detection.SmartFormatDetector class.
But the example goes no further. How do you use this information to dynamically parse a CSV file? It must have something to do with the DelimitedFileEngine but I cannot see how.
Update:
I figured out a possible way but had to resort to using reflection (which does not feel right). Is there another/better way? Maybe using System.Dynamic? Anyway, here is the code I have so far, it ain't pretty but it works:
// follows on from smart detector example
FileHelpers.Detection.RecordFormatInfo lDetectedFormat = formats[0];
Type lDetectedClass = lDetectedFormat.ClassBuilderAsDelimited.CreateRecordClass();
List<FieldInfo> lFieldInfoList = new List<FieldInfo>(lDetectedFormat.ClassBuilderAsDelimited.FieldCount);
foreach (FileHelpers.Dynamic.DelimitedFieldBuilder lField in lDetectedFormat.ClassBuilderAsDelimited.Fields)
lFieldInfoList.Add(lDetectedClass.GetField(lField.FieldName));
FileHelperAsyncEngine lFileEngine = new FileHelperAsyncEngine(lDetectedClass);
int lRecNo = 0;
lFileEngine.BeginReadFile(cReadingsFile);
try
{
while (true)
{
object lRec = lFileEngine.ReadNext();
if (lRec == null)
break;
Trace.WriteLine("Record " + lRecNo);
lFieldInfoList.ForEach(f => Trace.WriteLine(" " + f.Name + " = " + f.GetValue(lRec)));
lRecNo++;
}
}
finally
{
lFileEngine.Close();
}
As I use the SmartFormatDetector to determine the exact format of the incoming Delimited files you can use following appoach:
private DelimitedClassBuilder GetFormat(string file)
{
var detector = new FileHelpers.Detection.SmartFormatDetector();
var format = detector.DetectFileFormat(file);
return format.First().ClassBuilderAsDelimited;
}
private List<T> ConvertFile2Objects<T>(string file, out DelimitedFileEngine engine)
{
var format = GetSeperator(file); // Get Here your FormatInfo
engine = new DelimitedFileEngine(typeof(T)); //define your DelimitdFileEngine
//set some Properties of the engine with what you need
engine.ErrorMode = ErrorMode.SaveAndContinue; //optional
engine.Options.Delimiter = format.Delimiter;
engine.Options.IgnoreFirstLines = format.IgnoreFirstLines;
engine.Options.IgnoreLastLines = format.IgnoreLastLines;
//process
var ret = engine.ReadFileAsList(file);
this.errorCount = engine.ErrorManager.ErrorCount;
var err = engine.ErrorManager.Errors;
engine.ErrorManager.SaveErrors("errors.out");
//return records do here what you need
return ret.Cast<T>().ToList();
}
This is an approach I use in a project, where I only know that I have to process Delimited files of multiple types.
Attention:
I noticed that with the files I recieved the SmartFormatDetector has a problem with tab delimiter. Maybe this should be considered.
Disclaimer: This code is not perfected but in a usable state. Modification and/or refactoring is adviced.
I'm not a programmer so this is difficult for me. I want to make an extension to send the full path to the clipboard in the full format. Example:
D:\MyFolder\music\audio.mp3
I recently found and butchered this extension which sends the running time to the clipboard. Is it possible to modify it so it gets the full path instead of the running time?
I'm using VLC media player 2.0.5 Twoflower 32 bits.
Windows 7 professional 32bits SP1
Here's the content of the .lua file I'm using and want to modify:
-- Time2Clip.lua -- VLC extension --
--[[
INSTALLATION:
Put the file in the VLC subdir /lua/extensions, by default:
* Windows (all users): %ProgramFiles%\VideoLAN\VLC\lua\extensions\
Restart the VLC.
Then you simply use the extension by going to the "View" menu and selecting it.
--]]
function descriptor()
return {
title = "Time2Clip";
version = "1.0";
author = "valuex";
url = 'https://forum.videolan.org/viewtopic.php?f=29&t=101114';
shortdesc = "Time2Clip";
description = "<div style=\"background-color:lightgreen;\"><b>just a simple VLC extension </b></div>";
capabilities = {"input-listener"}
}
end
function activate()
create_dialog()
end
function close()
vlc.deactivate()
end
function create_dialog()
w = vlc.dialog("Time2Clip")
--w2 = w:add_button("Save_to_Clip", click_SAVE,2,1,1,1)
click_SAVE()
end
function click_SAVE()
local input = vlc.object.input()
if input then
local curtime=vlc.path()
-- local curtime=vlc.var.get(input, "time")
-- w2:set_text( curtime )
save_to_clipboard(curtime)
end
end
function save_to_clipboard(var)
strCmd = 'echo '..var..' |clip'
os.execute(strCmd)
vlc.deactivate()
end
I read LUA's README.TXT file and found this but I don't know how to use it. Please help me. Thanks in advance.
input.item(): Get the current input item. Input item methods are:
:uri(): Get item's URI.
:name(): Get item's name.
How about:
function descriptor()
return {
title = "URI2Clip";
version = "1.0";
author = "";
url = '';
shortdesc = "URI2Clip";
description = "<div><b>Copy the media URI to the Windows clipboard</b></div>";
}
end
function activate()
local item = vlc.input.item()
local uri = item:uri()
uri = string.gsub(uri, '^file:///', '')
uri = string.gsub(uri, '/', '\\')
strCmd = 'echo '..uri..' |clip'
os.execute(strCmd)
end
URI returns something like file:///c:/users/username/Documents/song.mp3 so I convert that to c:\users\username... format instead. NB. This is only going to work for saved files, it will mangle web addresses.
I am trying to do some simple pagination.
To that end, I'm trying to parse the current URL, then produce links to the same query, but with incremented and decremented page parameters.
I've tried doing the following, but it produces the same link, without the new page parameter.
var parts = url.parse(req.url, true);
parts.query['page'] = 25;
console.log("Link: ", url.format(parts));
The documentation for the URL module seems to suggest that format is what I need but I'm doing something wrong.
I know I could iterate and build up the string manually, but I was hoping there's an existing method for this.
If you look at the latest documentation, you can see that url.format behaves in the following way:
search will be used in place of query
query (object; see querystring) will only be used if search is absent.
And when you modify query, search remains unchanged and it uses it. So to force it to use query, simply remove search from the object:
var url = require("url");
var parts = url.parse("http://test.com?page=25&foo=bar", true);
parts.query.page++;
delete parts.search;
console.log(url.format(parts)); //http://test.com/?page=26&foo=bar
Make sure you're always reading the latest version of the documentation, this will save you a lot of trouble.
Seems to me like it's a bug in node. You might try
// in requires
var url = require('url');
var qs = require('querystring');
// later
var parts = url.parse(req.url, true);
parts.query['page'] = 25;
parts.query = qs.stringify(parts.query);
console.log("Link: ", url.format(parts));
The other answer is good, but you could also do something like this. The querystring module is used to work with query strings.
var querystring = require('querystring');
var qs = querystring.parse(parts.query);
qs.page = 25;
parts.search = '?' + querystring.stringify(qs);
var newUrl = url.format(parts);
To dry out code and get at URL variables without needing to require('url') I used:
/*
Used the url module to parse and place the parameters into req.urlparams.
Follows the same pattern used for swagger API path variables that load
into the req.params scope.
*/
app.use(function(req, res, next) {
var url = require('url');
var queryURL = url.parse(req.url, true);
req.urlparams = queryURL.query;
next();
});
var myID = req.urlparams.myID;
This will parse and move the url variables into the req.urlparams variable. It runs early in the request workflow so is available for all expressjs paths.