papa-parse
Polymer 2.0 element for CSV parsing with Papa parse.
[ This description is mirrored from README.md at github.com/PolymerVis/papa-parse on 2019-05-10 ]
papa-parse
<!-- download and parse into JSON -->
<papa-parse auto
url="https://rawgit.com/PolymerVis/papa-parse/master/demo/MOCK_DATA.csv"
rows="{{rows}}"></papa-parse>
<!-- render as a table -->
<h4>Parsed CSV table:</h4>
<table>
<template is="dom-repeat" items="[[rows]]" as="row">
<tr>
<template is="dom-repeat" items="[[row]]">
<td>[[item]]</td>
</template>
</tr>
</template>
</table>
<!-- unparse JSON into string -->
<papa-unparse header
json-array="[[rows]]"
csv-str="{{csvStr}}"></papa-unparse>
<!-- csv string output -->
<h4>Csv string</h4>
<pre>[[csvStr]]</pre>
Installation
bower install --save PolymerVis/papa-parse
Documentation and demos
More details @ webcomponents.org.
Disclaimers
PolymerVis is a personal project and is NOT in any way affliated with Papaparse, Polymer or Google.
papa-parse
papa-parse
is a Polymer 2.0 element to parse CSV files into JSON object(s)
with Papa parse.
papa-parse
can download and parse a csv file via url
, or from raw csv strings via raw
, and File object via file
. If the auto
flag is set, papa-parse
will automatically start the job, otherwise a manual call to the function start
will be needed.
Parse from URL.
<papa-parse auto url="MOCK_DATA.csv" rows="{{rows}}"></papa-parse>
Parse from raw csv String.
<papa-parse auto raw="[[SomeCsvString]]" rows="{{rows}}"></papa-parse>
Parse from FileReader
<input id="selectfile" type="file"></input>
<papa-parse auto file="[[file]]" rows="{{rows}}"></papa-parse>
this.$.selectfile
.addEventListener('change', function(e) {
this.file = e.target.files[0];
});
There are 2 possible outputs for rows
- an array of array of values, or an
array of objects. An array of array is returned if the header
flag is not
set, and an array of objects otherwise, where each object is a map comprising
of the column name and its corresponding value for the row
(e.g. {col1: value1, col2: value2}).
Handling big files
Parsing is synchronous and may block the UI thread (i.e. freeze the screen) if
the csv file is big. Parsing with a web-worker via worker
flag is recommended
for big file. However, note that papaparse.min.js
should not be bundled
during the build process if web-worker is required as the web-worker needs to
load the script. You will also need to correctly reference the location of the
script via the script-path
attribute.
You should not use relative path if parsing from url
, as the web-worker may
load from an incorrect path.
<papa-parse auto header worker stream
script-path="../../papaparse/papaparse.min.js"
fields="{{fields}}"
url="https://some.domain/some.csv"
on-stream="handleRecord"></papa-parse>
function handleRecord(e, {data, meta, errors}) {
console.log(data);
}
Streaming via stream
flag is also recommended for big file (stream
and
worker
are not dependent on each other). However, when stream
flag is set,
rows
attribute will only return an empty array as none of the records will be
persisted. Instead, papa-parse
will emit an stream
event of the form
{{data: Array[]|Object[], meta: Object, errors: Array, parser: Object}} for each
record parsed.
<button onclick="javascript:start()">[[buttonLabel]]</button>
<papa-parse id="parser"
stream
url="MOCK_DATA.csv"
rows="{{rows}}"
on-stream="handleRecord"></papa-parse>
function start() {
app.$.parser.start();
}
function handleRecord(e, {data, meta, errors}) {
alert(JSON.stringify(data));
app.$.parser.pause();
}
papa-unparse
papa-unparse
is a Polymer 2.0 element to convert JSON arrays or objects into
CSV strings with Papa parse.
Basic usage
For array of objects, e.g. [{col1: 1, col2: 2}, {col1: 3, col2: 4}]
<papa-unparse header json-array="[[rows]]"></papa-unparse>
For array of arrays, e.g. [[1,2], [3,4]]
<papa-unparse json-array="[[rows]]" fields="[[fields]]"></papa-unparse>
Download as CSV file
<papa-unparse header json-array="[[rows]]"></papa-unparse>
<button onclick="javascript:download">Download</button>
function download() {
document.querySelector('papa-unparse').downloadCsv('somefile.csv');
}
Other options
<papa-unparse
header
quotes
quoteChar="'"
delimiter="|"
newline="\n"
json-array="[[rows]]"></papa-unparse>
Links
Compatibility
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Version
Dependencies
Polymer/polymer#^2.0.0
- papaparse#^4.3.6
- Released
- 2017-10-10
- Maturity
- TESTED
- License
- Other
Compatibility
- Framework
- Polymer 2.0+
- Browser
- Browser Independent
papa-parse - Vaadin Add-on Directory
Polymer 2.0 element for CSV parsing with Papa parse.Parsed CSV table:
[[item]] |
Csv string
[[csvStr]]``` ## Installation ``` bower install --save PolymerVis/papa-parse ``` ## Documentation and demos More details @ [webcomponents.org](https://www.webcomponents.org/element/PolymerVis/papa-parse). ## Disclaimers PolymerVis is a personal project and is NOT in any way affliated with Papaparse, Polymer or Google. # papa-parse `papa-parse` is a Polymer 2.0 element to parse CSV files into JSON object(s) with [Papa parse](http://papaparse.com/). `papa-parse` can download and parse a csv file via `url`, or from raw csv strings via `raw`, and File object via `file`. If the `auto` flag is set, `papa-parse` will automatically start the job, otherwise a manual call to the function `start` will be needed. Parse from URL. ```html
Issue tracker
Online Demo
License
Documentation
View on GitHub
papa-parse version 2.0.0
### Dependencies
Polymer/polymer#^2.0.0
* papaparse#^4.3.6
papa-parse version 2.0.1
### Dependencies
Polymer/polymer#^2.0.0
* papaparse#^4.3.6