How to read a file inside a ZIP archive as string using JSZip

Want to read as an ArrayBuffer instead? Read How to read a file inside a ZIP archive as ArrayBuffer using JSZip

In JSZip, you can read a compressed file as JavaScript string using

zip.file("filename.txt").async("string").then(function(data) {
    // data is a string
    // TODO your code goes here, this is just an example
    console.log(data);
})

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. You can upload any .docx file for testing:

<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("string").then(function(data) {
                        // data is a string
                        // TODO Your code goes here!
                        console.log(data)
                    })
                }).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>