Question

您好我试图使用JS或Jquery计算文本文件中的所有非空行。

现在我正在使用两步法......但它仍在计算空白行。

我从输入框中拉出文本文件，并在文本区域上方显示文件信息，并在文本区域中显示内容。

Evertyhing似乎工作得很好，除了我不能让linecount.js跳过空行......这在jQuery中是否可能？

JS将文本文件加载到textarea：

   var reader; //GLOBAL File Reader object for demo purpose only

/**
 * Check for the various File API support.
 */
function checkFileAPI() {
    if (window.File && window.FileReader && window.FileList && window.Blob) {
        reader = new FileReader();
        return true; 
    } else {
        alert('The File APIs are not fully supported by your browser. Fallback required.');
        return false;
    }
}

/**
 * read text input
 */
function readText(filePath) {
    var output = ""; //placeholder for text output
    if(filePath.files && filePath.files[0]) {           
        reader.onload = function (e) {
            output = e.target.result;
            displayContents(output);
        };//end onload()
        reader.readAsText(filePath.files[0]);
    }//end if html5 filelist support
    else if(ActiveXObject && filePath) { //fallback to IE 6-8 support via ActiveX
        try {
            reader = new ActiveXObject("Scripting.FileSystemObject");
            var file = reader.OpenTextFile(filePath, 1); //ActiveX File Object
            output = file.ReadAll(); //text contents of file
            file.Close(); //close file "input stream"
            displayContents(output);
        } catch (e) {
            if (e.number == -2146827859) {
                alert('Unable to access local files due to browser security settings. ' + 
                 'To overcome this, go to Tools->Internet Options->Security->Custom Level. ' + 
                 'Find the setting for "Initialize and script ActiveX controls not marked as safe" and change it to "Enable" or "Prompt"'); 
            }
        }       
    }
    else { //this is where you could fallback to Java Applet, Flash or similar
        return false;
    }       
    return true;
}   

/**
 * display content using a basic HTML replacement
 */
function displayContents(txt) {
    var el = document.getElementById('countMe'); 
    el.innerHTML = txt; 

}

小数点的小提琴：

$(document).ready(function(){

var lines = 5;
var linesUsed = $('#linesUsed');

$('#countMe').keydown(function(e) {

    newLines = $(this).val().split("\n").length;
    linesUsed.text(newLines);

    if(e.keyCode == 13 && newLines >= lines) {
        linesUsed.css('color', 'red');
        return false;
    }
    else {
        linesUsed.css('color', '');
    }
});

}）;

输入代码和文本区域：

    <input type="file" id="files" name="files[]" onchange='readText(this)' />
   <textarea name="countMe" cols="58" rows="18" id="ta"></textarea>
   <div class="theCount">Lines used: <span id="linesUsed">0</span><div>

Answer 1

您正在计算行数但不检查每行中是否有任何内容。将行数组保留在变量中并循环遍历这些行以检查其中是否存在任何变化：

newLines = 0;
var lines = $(this).val().split("\n");
for (var i = 0; i < lines.length; i++) {
  if (lines[i].length > 0) newLines++;
}
linesUsed.text(newLines);

使用Javascript计算文本文件中的非空白行数？

1 个答案: