Question

我有一个包含另一个数组和字符串的数组：

var text;
var languageSet = ["Language4", "Language5"];
var languages = [
        ["Language1", "Language2", "Language3"],
        languageSet,
        "Language6"
    ];

(function selector() {
    for (i = 0; i < languages.length; i++) {
        for (j = 0; j < languages[i].length; j++) {
            text += "<option value='" + languages[i][j] + "'>" + languages[i][j] + "</options>";
        }
    }
    document.getElementById("languageOptions").innerHTML = text;
})();

HTML：

<select id="languageOptions">
</select>

但每次我运行时，＆＃34;语言6＆＃34;的输出最终成为这样：

L
a
n
g
u
a
g
e

6

如何输出整个字符串？我不知道为什么我的代码对数组中的字符串和数组不起作用。

Answer 1

您应该进行类型检查以查看您的项目是否为数组，然后循环数组。我在这里使用Array.isArray来进行类型检查。代码示例正在为您进行测试。

如果对象是数组，则Array.isArray（）方法返回true，否则返回false。

＆＃13;

$ python
Python 2.7.10 (default, Aug 22 2015, 20:33:39) 
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pymongo
>>> import mongoengine
>>>

＆＃13;

var text;
var languageSet = ["Language4", "Language5"];
var languages = [
        ["Language1", "Language2", "Language3"],
        languageSet,
        "Language6"
    ];


(function selector() {
    for (i = 0; i < languages.length; i++) {
      if (Array.isArray(languages[i])) {
        for (j = 0; j < languages[i].length; j++) {
          
            text += "<option value='" + languages[i][j] + "'>" + languages[i][j] + "</options>";
        }
      } else {
        text += "<option value='" + languages[i] + "'>" + languages[i] + "</options>";
      }
    }
    document.getElementById("languageOptions").innerHTML = text;
})();

＆＃13;

Answer 2

使用Array.isArray()函数检查循环内的类型。

from sage.all import *
import numpy as np
import random
import sage.all

def __NewTable__(C):
    A=np.array_str(C)
    word=""
    MS=[]
    for letter in A:
        if letter==')':
            word=''.join(letter)
            MS.append(word)
            word=""
        else:
            word=''.join(letter)
    return MS

length=int(raw_input("Give length of linear code"))
dimention=int(raw_input("Give the dimention"))
FF=int(raw_input("Give the finite field in which you want to work in"))
C = codes.ReedSolomonCode(length, dimention, GF(FF, "x"))
MS=__NewTable__(C)
print MS

Javascript嵌套数组与字符串

2 个答案: