ak.html

<!DOCTYPE html>
<html>

<head>
	<title>上传txt文件并读取第32行内容</title>
	<meta charset="utf-8">
	<script>
		var arr = [];

		function readContent(file) {
			var reader = new FileReader();
			reader.onload = function (e) {
				var lines = e.target.result.split('\n');
				var line32 = lines[31].match(/[0-9]+(\.[0-9]+)?/g);
				if (line32 != null) {
					for (var i = 0; i < line32.length; i++) {
						arr.push(parseFloat(line32[i]));
					}
				}
				updateNumberList();
			};
			reader.readAsText(file);
		}

		function handleFiles() {
			var files = document.getElementById("fileUpload").files;
			for (var i = 0; i < files.length; i++) {
				if (files[i].type === "text/plain") {
					readContent(files[i]);
				} else {
					alert("请选择txt文件");
				}
			}
		}

		function updateNumberList() {
			var numberList = document.getElementById("numberList");
			numberList.innerHTML = "";
			for (var i = 0; i < arr.length; i++) {
				var li = document.createElement("li");
				li.innerText = arr[i];
				numberList.appendChild(li);
			}
		}
	</script>
</head>

<body>
	<input type="file" id="fileUpload" multiple onchange="handleFiles()">
	<p>已读取的数字：</p>
	<ul id="numberList"></ul>
	<script>
		updateNumberList();
	</script>
</body>

</html>