In JSZip, you can get the file size of a file compressed inside a ZIP archive by first decompressing it using zip.file(...).async(...) into an ArrayBuffer and then using .byteLength to get the size of the buffer.
zip.file("filename.txt").async("ArrayBuffer").then(function(data) {
var fileSize = data.byteLength;
// TODO Your code goes here
})Full example
This is based on our post on How to uncompress file inside ZIP archive using HTML5 & JSZip which reads a local file using a HTML5 file input. This example prints the file size of every file inside the ZIP archive:
<html>
<body>
<input type="file" id="myfile" onchange="onMyfileChange(this)" />
<script src="https://unpkg.com/[email protected]/dist/jszip.js" type="text/javascript"></script>
<script type="text/javascript">
function onMyfileChange(fileInput) {
if(fileInput.files[0] == undefined) {
return ;
}
var filename = fileInput.files[0].name;
var reader = new FileReader();
reader.onload = function(ev) {
JSZip.loadAsync(ev.target.result).then(function(zip) {
zip.file("word/document.xml").async("ArrayBuffer").then(function(data) {
console.log("word/document.xml is", data.byteLength, "bytes long");
})
}).catch(function(err) {
console.error("Failed to open", filename, " as ZIP file:", err);
})
};
reader.onerror = function(err) {
console.error("Failed to read file", err);
}
reader.readAsArrayBuffer(fileInput.files[0]);
}
</script>
</body>
</html>Example output
word/document.xml is 88369 bytes long