如何将对象数组中的特定键作为 for 循环内条件的目标？

Question

JS 新手！尝试为我的对象中的一个键指定一个语句，该对象再次嵌套在一个数组中。在 Slowbro 旁边 - 应显示消息：“哇，这是一只大口袋妖怪”，但这不起作用。我试图在我的 for 循环中为所有口袋妖怪写一个一般条件，但也指定“哇，这是一个大口袋妖怪”消息应该只出现在 Slowbro 而不是任何满足 height>1.5 标准的人。我错过了什么？

//Array contains Pokemon data to display in application
//Each object represents one Pokemon with respective properties
let pokemonList = [
        {name:'Pikachu', height: 0.4, type:['electric','ground','steel','flying']},
        {name:'Charmeleon', height: 1.1, type:['ground','rock', 'water']},
        {name: 'Slowbro' ,height: 1.6, type:['electric', 'grass','dragon','ghost','bug']}
      ];

//Loop lists each Pokemon in array by assigning name and height keys 
for (let i=0; i < pokemonList.length; i++) 
  { document.write(pokemonList[i].name+ ' (height: ' + pokemonList[i].height + ') ' + '<br>')
  }



for (let i=0; i < pokemonList[i].length; i++) {
  if (pokemonList[i].height > 1.5 && pokemonList[i].name === 'Slowbro') {
    console.log('- Wow, this is a big Pokemon!');
    } else if (pokemonList[i].height > 0.5 && pokemonList[i].height < 1.5) {
    console.log('- This is an average size Pokemon.');
    } else {
    console.log('- This is a small Pokemon.')
    }
}

Answer 1

在代码段的最后一个 for 循环中，您使用的不是数组的长度，而是第一个元素的长度：

for (let i=0; i < pokemonList[a].length; i++)

您可能需要数组本身的长度：

for (let i=0; i < pokemonList.length; i++)

相反。

//Array contains Pokemon data to display in application
//Each object represents one Pokemon with respective properties
let pokemonList = [
        {name:'Pikachu', height: 0.4, type:['electric','ground','steel','flying']},
        {name:'Charmeleon', height: 1.1, type:['ground','rock', 'water']},
        {name: 'Slowbro' ,height: 1.6, type:['electric', 'grass','dragon','ghost','bug']}
      ];

//Loop lists each Pokemon in array by assigning name and height keys 
for (let i=0; i < pokemonList.length; i++) 
  { document.write(pokemonList[i].name+ ' (height: ' + pokemonList[i].height + ') ' + '<br>')
  }



for (let i=0; i < pokemonList.length; i++) {
  if (pokemonList[i].height > 1.5 && pokemonList[i].name === 'Slowbro') {
    console.log('- Wow, this is a big Pokemon!');
    } else if (pokemonList[i].height > 0.5 && pokemonList[i].height < 1.5) {
    console.log('- This is an average size Pokemon.');
    } else {
    console.log('- This is a small Pokemon.')
    }
}

Answer 2

试试这个

//Array contains Pokemon data to display in application
//Each object represents one Pokemon with respective properties
let pokemonList = [
        {name:'Pikachu', height: 0.4, type:['electric','ground','steel','flying']},
        {name:'Charmeleon', height: 1.1, type:['ground','rock', 'water']},
        {name: 'Slowbro' ,height: 1.6, type:['electric', 'grass','dragon','ghost','bug']}
      ];

const html = pokemonList.map(({name, height}) => {
   return `${name} (height: ${height})`
}).join('<br>')

document.write(html)

pokemonList.forEach(({name, height}) => {
  if( height > 1.5){
    console.log('- Wow, this is a big Pokemon!')
  }else if(height > 0.5){
    console.log('- This is an average size Pokemon.');
  } else {
    console.log('- This is a small Pokemon.')
  }
})

如何将对象数组中的特定键作为 for 循环内条件的目标？

How do I target a specific key in an array of objects for a conditional inside a for loop?

javascript

for-loop

if-statement

conditional-statements