我在下面的代码中,用户可以上传文本文件。使用div作为分割字符分割输出后,我尝试在@中显示输出。存储在变量中的数组元素在alert中正确显示为换行,但在div中以一行显示。



  function readBlob(opt_startByte, opt_stopByte) {

    var files = document.getElementById('files').files;
    if (!files.length) {
      alert('Please select a file!');
      return;
    }
    var file = files[0];
    var start = parseInt(opt_startByte) || 0;
    var stop = parseInt(opt_stopByte) || file.size - 1;
    var reader = new FileReader();

    // If we use onloadend, we need to check the readyState.
    reader.onloadend = function(evt) {
      if (evt.target.readyState == FileReader.DONE) { // DONE == 2
	  	var test = evt.target.result;
		var htmlstring = test.split('@');
		var data = htmlstring.join('\r\n');
        document.getElementById('byte_content').textContent = data;
		alert(data); //with line-break
		alert(htmlstring); // without line-break
      }
    };
    var blob = file.slice(start, stop + 1);
    reader.readAsBinaryString(blob);
  }
  document.querySelector('.readBytesButtons').addEventListener('click', function(evt) {
    if (evt.target.tagName.toLowerCase() == 'button') {
      var startByte = evt.target.getAttribute('data-startbyte');
      var endByte = evt.target.getAttribute('data-endbyte');
      readBlob(startByte, endByte);
    }
  }, false);
 

  #byte_content {
    margin: 5px 0;
    max-height: 100px;
    overflow-y: auto;
    overflow-x: hidden;
  }
  #byte_range { margin-top: 5px; }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="file" id="files" name="file" /> Read bytes:
<span class="readBytesButtons">
  <button>entire file</button>
</span>
<div id="byte_content"></div>





文本文件数据:

this is some text @2135311 164 @df fdg


电流输出:

this is some text 2135311 164 df fdg


所需的输出:

this is some text
2135311 164
df fdg

最佳答案

您需要以HTML而非纯文本格式呈现数据:
代替\r\n使用<br>
代替.textContent使用innerHTML


var data = htmlstring.join('<br>');
document.getElementById('byte_content').innerHTML = data;



演示版



function readBlob(opt_startByte, opt_stopByte) {

  var files = document.getElementById('files').files;
  if (files.length < 1) {
    alert('Please select a file!');
    return;
  }
  var file = files[0];
  var start = parseInt(opt_startByte) || 0;
  var stop = parseInt(opt_stopByte) || file.size - 1;
  var reader = new FileReader();

  // If we use onloadend, we need to check the readyState.
  reader.onloadend = function(evt) {
    if (evt.target.readyState == FileReader.DONE) { // DONE == 2
      var test = evt.target.result;
      var htmlstring = test.split('@');
      var data = htmlstring.join('<br>');
      document.getElementById('byte_content').innerHTML = data;
      alert(data); //with line-break
      alert(htmlstring); // without line-break
    }
  };
  var blob = file.slice(start, stop + 1);
  reader.readAsBinaryString(blob);
}
document.querySelector('.readBytesButtons').addEventListener('click', function(evt) {
  if (evt.target.tagName.toLowerCase() == 'button') {
    var startByte = evt.target.getAttribute('data-startbyte');
    var endByte = evt.target.getAttribute('data-endbyte');
    readBlob(startByte, endByte);
  }
}, false);

#byte_content {
  margin: 5px 0;
  max-height: 100px;
  overflow-y: scroll;
  overflow-x: hidden;
}

#byte_range {
  margin-top: 5px;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<input type="file" id="files" name="file" /> Read bytes:
<span class="readBytesButtons">
  <button>entire file</button>
</span>
<div id="byte_content"></div>

关于javascript - 将数组(从文本文件读取和处理)元素显示到JavaScript中的新行,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/52860709/

10-12 12:50
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