表中的元素由於未被捕獲的錯誤而未被讀取

Question

我非常沮喪於一個項目中，如果表中有重複的元素，我想隱藏它們。我發現重複沒有問題。當我嘗試隱藏重複項時，問題就開始了。我使用的是沒有任何框架工程或庫的香草JavaScript。我得到這個很難破譯的錯誤。

Uncaught Type Error: Cannot read property 'e' of undefined

e是表

我沒有在我的HTML任何硬編碼的數據第一個重複的元素 - 這是所有的JavaScript。我從來沒有這樣做過，所以我想我會伸出一些幫助。我的代碼如下。

欣賞您的幫助提前。

var data = [ 
 
    ['e', 0, 1, 2, 3, 4], 
 
    ['a', 54312, 235, 5, 15, 4], 
 
    ['a', 6, 7, 8, 9, 232], 
 
    ['a', 54, 11235, 345, 5, 6], 
 
    ['b', 0, 1, 2, 3, 4], 
 
    ['b', 54312, 235, 5, 15, 4], 
 
    ['c', 62, 15, 754, 93, 323], 
 
    ['d', 27, 11235, 425, 18, 78], 
 
    ['d', 0, 1, 2, 3, 4], 
 
    ['d', 54312, 235, 5, 15, 4], 
 
    ['e', 6, 7, 8, 9, 232], 
 
    ['e', 54, 11235, 345, 5, 6], 
 
    ['e', 0, 1, 2, 3, 4], 
 
    ['e', 54312, 235, 5, 15, 4], 
 
    ['e', 62, 15, 754, 93, 323], 
 
    ['e', 27, 11235, 425, 18, 78] 
 
]; 
 

 

 

 

 

 
//Create a HTML Table element. 
 
var table = document.createElement("TABLE"); 
 
var elems = document.getElementsByClassName("tableRow"); 
 

 

 
//Get the count of columns. 
 
var columnCount = data[0].length; 
 

 

 
//Add the data rows. 
 

 
for (var i = 0; i < data.length; i++) { 
 
    var row = table.insertRow(-1); 
 
    for (var j = 0; j < columnCount; j++) { 
 
    //Searching for duplicates    
 
    var num = data[i][0]; 
 
    for (var otherRow = i + 1; otherRow < data.length; otherRow++) { 
 
     var dup = data[otherRow][0]; 
 
     console.log("What is the dup" + dup); 
 
     if (num === dup) { 
 
     console.log("duplicate"); 
 
     elems.data[dup].style.display = "none"; 
 

 
     } 
 
    } 
 

 

 
    var cell = row.insertCell(-1); 
 
    cell.innerHTML = data[i][j]; 
 
    cell.innerHtml = myZero; 
 

 
    } 
 
} 
 

 

 
var dvTable = document.getElementById("dvTable"); 
 
dvTable.innerHTML = ""; 
 
dvTable.appendChild(table);

Answer 1

你可以單獨去重和實際創建從您的數據元素。使用Array.filter您可以刪除所有重複項，以便在插入時不必擔心。

var data = [ 
 
    ['e', 0, 1, 2, 3, 4], 
 
    ['a', 54312, 235, 5, 15, 4], 
 
    ['a', 6, 7, 8, 9, 232], 
 
    ['a', 54, 11235, 345, 5, 6], 
 
    ['b', 0, 1, 2, 3, 4], 
 
    ['b', 54312, 235, 5, 15, 4], 
 
    ['c', 62, 15, 754, 93, 323], 
 
    ['d', 27, 11235, 425, 18, 78], 
 
    ['d', 0, 1, 2, 3, 4], 
 
    ['d', 54312, 235, 5, 15, 4], 
 
    ['e', 6, 7, 8, 9, 232], 
 
    ['e', 54, 11235, 345, 5, 6], 
 
    ['e', 0, 1, 2, 3, 4], 
 
    ['e', 54312, 235, 5, 15, 4], 
 
    ['e', 62, 15, 754, 93, 323], 
 
    ['e', 27, 11235, 425, 18, 78] 
 
]; 
 

 

 
var alreadyFound = []; 
 

 
data = data.filter(function(item, pos, arr) { 
 
    var key = item[0]; 
 
    // If we have already found this character, then skip. 
 
    if (alreadyFound.indexOf(key) > -1) return false; 
 
    // Otherwise, add this char to alreadyFound and include the item. 
 
    alreadyFound.push(key); 
 
    return true; 
 
}); 
 

 

 
//Create a HTML Table element. 
 
var table = document.createElement("TABLE"); 
 
var elems = document.getElementsByClassName("tableRow"); 
 

 

 
//Get the count of columns. 
 
var columnCount = data[0].length; 
 

 

 
//Add the data rows. 
 

 
for (var i = 0; i < data.length; i++) { 
 
    var row = table.insertRow(-1); 
 
    for (var j = 0; j < columnCount; j++) { 
 
    var cell = row.insertCell(-1); 
 
    cell.innerHTML = data[i][j]; 
 
    } 
 
} 
 

 

 
var dvTable = document.getElementById("dvTable"); 
 
dvTable.innerHTML = ""; 
 
dvTable.appendChild(table);

<div id="dvTable"></div>

Answer 2

我用紅色水銀同意。你首先需要刪除數組中的重複項。 紅色水星答案是完全有效的，但這裏是一個骯髒的快速多維陣列重複數據刪除功能，我正在使用這種東西。

var data = [ 
    ['e', 0, 1, 2, 3, 4], 
    ['a', 54312, 235, 5, 15, 4], 
    ['a', 6, 7, 8, 9, 232], 
    ['a', 54, 11235, 345, 5, 6], 
    ['b', 0, 1, 2, 3, 4], 
    ['b', 54312, 235, 5, 15, 4], 
    ['c', 62, 15, 754, 93, 323], 
    ['d', 27, 11235, 425, 18, 78], 
    ['d', 0, 1, 2, 3, 4], 
    ['d', 54312, 235, 5, 15, 4], 
    ['e', 6, 7, 8, 9, 232], 
    ['e', 54, 11235, 345, 5, 6], 
    ['e', 0, 1, 2, 3, 4], 
    ['e', 54312, 235, 5, 15, 4], 
    ['e', 62, 15, 754, 93, 323], 
    ['e', 27, 11235, 425, 18, 78] 
]; 

function multiDimlUniq(arr) { 
    var uniques = []; 
    var founds = {}; 
    for (var i = 0, l = arr.length; i < l; i++) { 
     var s = JSON.stringify(arr[i]); 
     if (founds[s]) { 
      continue; 
     } 
     uniques.push(arr[i]); 
     founds[s] = true; 
    } 
    return uniques; 
} 

var reduced = multiDimlUniq(data)