javascript - 当我指定一定数量的列时，乘法表不起作用

Question

我不明白为什么当我指定的列数少于行数时，HTML 表格无法构建。

var table2 = Array(10);
for (var i = 0; i < table2.length; i++) {

// If I change Array(5) to something like Array(10) it doesn't work
table2[i] = Array(5);
}


var code = "<table cellpadding=\"15\" cellspacing=\"0\"><tr>"

for (row = 1; row <= table2.length; row++) {
  for (col = 1; col <= table2[col].length; col++) {
    code += "<td>" + col * row + "</td>";
  }
code += "</tr>";
};

document.getElementById('fart').innerHTML = code;

链接:https://jsfiddle.net/pz4p9nff/

Answer 1

代码中的以下更正将解决您面临的问题。

var table2 = Array(10); //Init the amount of rows in your table
var code = "<table cellpadding=\"15\" cellspacing=\"0\">";

//Don't forget: arrays are zero based. Starting at 1 will skip row with index 0
for (row = 0; row < table2.length; row++){

    //Initialize each row with a fixed amount of columns... 
  //no need to do this in a seperate loop
    table2[row] = Array(5); 
  //Open each row properly
  code += "<tr>"; 

  //Loop the columns of each row
  for (col = 0; col < table2[row].length; col++){
    code += "<td>" + col*row + "</td>";
  }

  code += "</tr>";
};

code += "</table>"; //Close your table properly

document.getElementById('fart').innerHTML = code;