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javascript - for循环嵌套数组长度无法读取属性错误

问题描述

我试图在这个函数中循环这个嵌套数组，当我在 findIndividualCards 函数'let checkArray = array[array.length - 1]'中调用 validateCred 函数时得到这个错误 ^

'TypeError：无法读取未定义的属性'长度''

这是代码

// All valid credit card numbers
const valid1 = [4, 5, 3, 9, 6, 7, 7, 9, 0, 8, 0, 1, 6, 8, 0, 8];
const valid2 = [5, 5, 3, 5, 7, 6, 6, 7, 6, 8, 7, 5, 1, 4, 3, 9];
const valid3 = [3, 7, 1, 6, 1, 2, 0, 1, 9, 9, 8, 5, 2, 3, 6];
const valid4 = [6, 0, 1, 1, 1, 4, 4, 3, 4, 0, 6, 8, 2, 9, 0, 5];
const valid5 = [4, 5, 3, 9, 4, 0, 4, 9, 6, 7, 8, 6, 9, 6, 6, 6];

// All invalid credit card numbers
const invalid1 = [4, 5, 3, 2, 7, 7, 8, 7, 7, 1, 0, 9, 1, 7, 9, 5];
const invalid2 = [5, 7, 9, 5, 5, 9, 3, 3, 9, 2, 1, 3, 4, 6, 4, 3];
const invalid3 = [3, 7, 5, 7, 9, 6, 0, 8, 4, 4, 5, 9, 9, 1, 4];
const invalid4 = [6, 0, 1, 1, 1, 2, 7, 9, 6, 1, 7, 7, 7, 9, 3, 5];
const invalid5 = [5, 3, 8, 2, 0, 1, 9, 7, 7, 2, 8, 8, 3, 8, 5, 4];

// Can be either valid or invalid
const mystery1 = [3, 4, 4, 8, 0, 1, 9, 6, 8, 3, 0, 5, 4, 1, 4];
const mystery2 = [5, 4, 6, 6, 1, 0, 0, 8, 6, 1, 6, 2, 0, 2, 3, 9];
const mystery3 = [6, 0, 1, 1, 3, 7, 7, 0, 2, 0, 9, 6, 2, 6, 5, 6, 2, 0, 3];
const mystery4 = [4, 9, 2, 9, 8, 7, 7, 1, 6, 9, 2, 1, 7, 0, 9, 3];
const mystery5 = [4, 9, 1, 3, 5, 4, 0, 4, 6, 3, 0, 7, 2, 5, 2, 3];

// An array of all the arrays above
const batch = [valid1, valid2, valid3, valid4, valid5, invalid1, invalid2, invalid3, invalid4, invalid5, mystery1, mystery2, mystery3, mystery4, mystery5];


// Add your functions below:
function validateCred(array){
  let checkArray = array[array.length - 1]
  array.pop()
  for(let i = array.length - 1; i >= 0; i--){
    if(array.indexOf([i]) % 2 != 0){
      let oddArray = array[i] *= 2;
      if(oddArray > 9){
        oddArray -= 9;
      }
    }
    array.push(checkArray);
    let total = 0
    for(let j = 0; j < array.length; j++){
      total += array[j];
      if(total % 10 === 0){
    return 'Valid';
  } else {
    return 'Invalid';
  }
  }
}
}
console.log(validateCred(invalid2))


function findInvalidCards(array){
  let invalidCards = []
  for(let i = 0; i < array.length; i++){
    for(let j = 0; j < array[i].length; j++){
      validateCred(array[j])
      if(array[j] === 'Invalid'){
        invalidCards.push(array[j])
      }
     
    }

}
 return invalidCards;
}


console.log(findInvalidCards(batch))

标签： javascriptarraysloopsfor-loop

解决方案

我认为在 findInvalidCards 中使用的循环中存在逻辑错误。我不是 100% 确定您的 validateCred() 在做什么，但这可能会帮助您找到问题。注意那条if(validateCred(array[i]) === 'Invalid')线。

function findInvalidCards(array){
  let invalidCards = []
  for(let i = 0; i < array.length; i++){
    for(let j = 0; j < array[i].length; j++){
      if(validateCred(array[i]) === 'Invalid'){
        invalidCards.push(array[j])
      }
    }
  }
  return invalidCards;
}

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