Javascript else if语句即使在满足要求的情况下也不运行？ 函数非法\u chr（输入）{ //检查“输入框”中是否有非法字符 document.getElementById（“binary_p”）.innerHTML=“将二进制转换为文本或将文本转换为二进制。” var entry_value=document.getElementById（“entry_box”）.value； var entry\u length=entry\u value.length 变量字符\u数组=[] var非法\u message\u bin=“请确保您只使用了二进制。” var非法_-BIN=[“a”、“b”、“c”、“d”、“e”、“f”、“g”、“h”、“i”、“j”、“k”、“l”、“m”、“n”、“o”、“p”、“q”、“r”、“s”、“t”、“u”、“v”、“w”、“x”、“y”、“z”、“[”、“、”、“、”、“、”、“、“、”、“、“、”、“、“>”、“

使用==”和！==进行比较

我的猜测是，您假设条件满足，但JavaScript告诉您不满足。请检查您的假设

---

这不是一个简单的问题吗？

使用===和！==进行比较

我的猜测是，您假设条件满足，但JavaScript告诉您不满足。请检查您的假设

---

这不是一个简单的问题吗？

使用===和！==进行比较

我的猜测是，您假设条件满足，但JavaScript告诉您不满足。请检查您的假设

---

这不是一个简单的问题吗？

使用===和！==进行比较

我的猜测是，您假设条件满足，但JavaScript告诉您不满足。请检查您的假设

---

这不是一个简单的问题吗？

只是一个提示，您可以使用正则表达式，如@duffymo所述：

function illegal_chr(input) {
//checks 'entry_box' for illegal characters
document.getElementById("binary_p").innerHTML = "Convert binary to text or text to binary."
var entry_value = document.getElementById("entry_box").value;
var entry_length = entry_value.length
var CHARACTERS_ARRAY = []
var illegal_message_bin = "Please ensure you have only used binary."
var ILLEGAL_BIN = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "[", "]", "#", "'", ";", ",", ".", "`", "¬", "?", ">", "<", "~", "@", ":", "}", "{", "|", "/", "!", "£", "$", "%", "^", "&", "*", "(", ")", "_", "-", "+", "=", "2", "3", "4", "5", "6", "7", "8", "9"]

//adds each character to 'CHARACTERS_ARRAY'
for (var c = 0; c < entry_length; c += 1) {
    character = entry_value[c];

    CHARACTERS_ARRAY.push(character)
}

//loops through 'CHARACTERS_ARRAY' checking for any illegal characters
for (var ch = 0; ch < CHARACTERS_ARRAY.length; ch += 1) {
    characters = CHARACTERS_ARRAY[ch];

    for (var ill = 0; ill < ILLEGAL_BIN.length; ill += 1) {
        letters = ILLEGAL_BIN[ill]

        if (characters == letters) {
            document.getElementById("binary_p").innerHTML = illegal_message_bin;
        }

        else if (characters != letters && ch == entry_length) {
            alert("test")
        }
    }
}
}

这将检查二进制数（至少一个0或1）：

---

请注意，您可以使用正则表达式，正如@duffymo所说：

function illegal_chr(input) {
//checks 'entry_box' for illegal characters
document.getElementById("binary_p").innerHTML = "Convert binary to text or text to binary."
var entry_value = document.getElementById("entry_box").value;
var entry_length = entry_value.length
var CHARACTERS_ARRAY = []
var illegal_message_bin = "Please ensure you have only used binary."
var ILLEGAL_BIN = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "[", "]", "#", "'", ";", ",", ".", "`", "¬", "?", ">", "<", "~", "@", ":", "}", "{", "|", "/", "!", "£", "$", "%", "^", "&", "*", "(", ")", "_", "-", "+", "=", "2", "3", "4", "5", "6", "7", "8", "9"]

//adds each character to 'CHARACTERS_ARRAY'
for (var c = 0; c < entry_length; c += 1) {
    character = entry_value[c];

    CHARACTERS_ARRAY.push(character)
}

//loops through 'CHARACTERS_ARRAY' checking for any illegal characters
for (var ch = 0; ch < CHARACTERS_ARRAY.length; ch += 1) {
    characters = CHARACTERS_ARRAY[ch];

    for (var ill = 0; ill < ILLEGAL_BIN.length; ill += 1) {
        letters = ILLEGAL_BIN[ill]

        if (characters == letters) {
            document.getElementById("binary_p").innerHTML = illegal_message_bin;
        }

        else if (characters != letters && ch == entry_length) {
            alert("test")
        }
    }
}
}

这将检查二进制数（至少一个0或1）：

---

请注意，您可以使用正则表达式，正如@duffymo所说：

function illegal_chr(input) {
//checks 'entry_box' for illegal characters
document.getElementById("binary_p").innerHTML = "Convert binary to text or text to binary."
var entry_value = document.getElementById("entry_box").value;
var entry_length = entry_value.length
var CHARACTERS_ARRAY = []
var illegal_message_bin = "Please ensure you have only used binary."
var ILLEGAL_BIN = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "[", "]", "#", "'", ";", ",", ".", "`", "¬", "?", ">", "<", "~", "@", ":", "}", "{", "|", "/", "!", "£", "$", "%", "^", "&", "*", "(", ")", "_", "-", "+", "=", "2", "3", "4", "5", "6", "7", "8", "9"]

//adds each character to 'CHARACTERS_ARRAY'
for (var c = 0; c < entry_length; c += 1) {
    character = entry_value[c];

    CHARACTERS_ARRAY.push(character)
}

//loops through 'CHARACTERS_ARRAY' checking for any illegal characters
for (var ch = 0; ch < CHARACTERS_ARRAY.length; ch += 1) {
    characters = CHARACTERS_ARRAY[ch];

    for (var ill = 0; ill < ILLEGAL_BIN.length; ill += 1) {
        letters = ILLEGAL_BIN[ill]

        if (characters == letters) {
            document.getElementById("binary_p").innerHTML = illegal_message_bin;
        }

        else if (characters != letters && ch == entry_length) {
            alert("test")
        }
    }
}
}

这将检查二进制数（至少一个0或1）：

---

请注意，您可以使用正则表达式，正如@duffymo所说：

function illegal_chr(input) {
//checks 'entry_box' for illegal characters
document.getElementById("binary_p").innerHTML = "Convert binary to text or text to binary."
var entry_value = document.getElementById("entry_box").value;
var entry_length = entry_value.length
var CHARACTERS_ARRAY = []
var illegal_message_bin = "Please ensure you have only used binary."
var ILLEGAL_BIN = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "[", "]", "#", "'", ";", ",", ".", "`", "¬", "?", ">", "<", "~", "@", ":", "}", "{", "|", "/", "!", "£", "$", "%", "^", "&", "*", "(", ")", "_", "-", "+", "=", "2", "3", "4", "5", "6", "7", "8", "9"]

//adds each character to 'CHARACTERS_ARRAY'
for (var c = 0; c < entry_length; c += 1) {
    character = entry_value[c];

    CHARACTERS_ARRAY.push(character)
}

//loops through 'CHARACTERS_ARRAY' checking for any illegal characters
for (var ch = 0; ch < CHARACTERS_ARRAY.length; ch += 1) {
    characters = CHARACTERS_ARRAY[ch];

    for (var ill = 0; ill < ILLEGAL_BIN.length; ill += 1) {
        letters = ILLEGAL_BIN[ill]

        if (characters == letters) {
            document.getElementById("binary_p").innerHTML = illegal_message_bin;
        }

        else if (characters != letters && ch == entry_length) {
            alert("test")
        }
    }
}
}

这将检查二进制数（至少一个0或1）：

这大致相当于

if(conditionA){
//do something
}
else if(conditionB){
//do something else
}

在这里的“else if conditional”中，它自动表示满足条件“characters！=字母”

if(conditionA){
//do something
}
**if(!conditionA && conditionB)**{
//do something else
}

因此可以写成

else if (characters != letters && ch == entry_length)

在for循环的每次迭代中，ch引用字符数组的每个元素

• 您已经在输入框输入元素中输入了文本abc

• 这意味着变量项_值包含字符串“abc”

• 条目长度包含3[您输入的文本长度]

• 继续您的代码，字符_数组包含数组['a'，'b'，'c']

• 字符的数组长度也是3

---

for循环开始 -对于循环迭代1:ch包含0 -对于循环迭代2:ch包含1 -对于循环迭代3:ch包含2 用于循环结束

输入长度为3，因此永远不会等于变化的ch&您永远不会看到警报

正如duffymo所建议的那样，使用正则表达式做这件事非常简单

这大致相当于

if(conditionA){
//do something
}
else if(conditionB){
//do something else
}

在这里的“else if conditional”中，它自动表示满足条件“characters！=字母”

if(conditionA){
//do something
}
**if(!conditionA && conditionB)**{
//do something else
}

因此可以写成

else if (characters != letters && ch == entry_length)

在for循环的每次迭代中，ch引用字符数组的每个元素

• 您已经在输入框输入元素中输入了文本abc

• 这意味着变量项_值包含字符串“abc”

• 条目长度包含3[您输入的文本长度]

• 继续您的代码，字符_数组包含数组['a'，'b'，'c']

• 字符的数组长度也是3

---

for循环开始 -对于循环迭代1:ch包含0 -对于循环迭代2:ch包含1 -对于循环迭代3:ch包含2 用于循环结束

输入长度为3，因此永远不会等于变化的ch&您永远不会看到警报

正如duffymo所建议的那样，使用正则表达式做这件事非常简单

这大致相当于

if(conditionA){
//do something
}
else if(conditionB){
//do something else
}

在这里的“else if conditional”中，它自动表示满足条件“characters！=字母”

if(conditionA){
//do something
}
**if(!conditionA && conditionB)**{
//do something else
}

因此可以写成

else if (characters != letters && ch == entry_length)

在for循环的每次迭代中，ch引用字符数组的每个元素

• 您已经在输入框输入元素中输入了文本abc

• 这意味着变量项_值包含字符串“abc”

• 条目长度包含3[您输入的文本长度]

• 继续您的代码，字符_数组包含数组['a'，'b'，'c']

• 字符的数组长度也是3

---

for循环开始 -对于循环迭代1:ch包含0 -对于循环迭代2:ch包含1 -对于循环迭代3:ch包含2 用于循环结束

输入长度为3，因此永远不会等于变化的ch&您永远不会看到警报

正如duffymo所建议的那样，使用正则表达式做这件事非常简单

这大致相当于

if(conditionA){
//do something
}
else if(conditionB){
//do something else
}

在这里的“else if conditional”中，它自动表示满足条件“characters！=字母”

if(conditionA){
//do something
}
**if(!conditionA && conditionB)**{
//do something else
}

因此可以写成

else if (characters != letters && ch == entry_length)

在for循环的每次迭代中，ch引用字符数组的每个元素

• 您已经在输入框输入元素中输入了文本abc

• 这意味着变量项_值包含字符串“abc”

• 条目长度包含3[您输入的文本长度]

• 继续您的代码，字符_数组包含数组['a'，'b'，'c']

• 字符的数组长度也是3

---

for循环开始 -为了