javascript 类型错误：表达式 'input.replace' [undefined] 的结果不是函数
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TypeError: Result of expression 'input.replace' [undefined] is not a function
提问by Frederik Kammer
I wrote the following function in javascript:
我在javascript中编写了以下函数：
function maskString(input) {
return input.replace(/\s\s+/," ");
}
Very simple. In a second function I wrote:
很简单的。在第二个函数中，我写道：
function secondFunction(string1, string2) { //Attetion! See Update 2!
var string1masked = maskString(string1);
var string2masked = maskString(string2);
( ... )
}
The error message is:
TypeError: Result of expression 'input.replace' [undefined] is not a function.
错误信息是：
TypeError: Result of expression 'input.replace' [undefined] is not a function.
Anybody an idea? Google wasn't really helpful :\
有人有想法吗？谷歌并没有真正的帮助：\
UPDATE 1:
I'm using jQuery and string1 is from an textbox. I'm calling the second function like this:
更新 1：
我正在使用 jQuery，而 string1 来自文本框。我正在像这样调用第二个函数：
var bool = secondFunction (textarea1.val(), textarea2.val()); //Attetion! See Update 2!
UPDATE 2:
I was wrong with the second function ... It's:
更新 2：
我对第二个功能有误......它是：
function secondFunction(string1, array1) {
var string1masked = maskString(string1);
var array1masked = maskString(array1);
( ... )
}
So my function doesn't work with the array. Unfortunately I have no idea how to change it :(
所以我的函数不适用于数组。不幸的是我不知道如何改变它:(
采纳答案by Lekensteyn
I guess you have code like this:
我猜你有这样的代码：
var textarea1 = $("#textarea1");
textarea1.val()returns undefinedif the element is not found (i.e. an element with ID textarea1). Check if you haven't made a typo in the element selector and if the function is called after the element is available.
textarea1.val()返回undefined如果未找到该元件（即，具有ID的元素textarea1）。检查您是否在元素选择器中没有打错字，以及是否在元素可用后调用该函数。
This function works for strings and arrays containing strings. If an argument or array value is not a string nor an array, it does not touch the value.
此函数适用于字符串和包含字符串的数组。如果参数或数组值既不是字符串也不是数组，则不会触及该值。
function maskData(input) {
// edit strings
if (typeof input == "string") return input.replace(/\s\s+/, "");
// if 'input' is an array, iterate through its elements and pass it to maskData again
if (input instanceof Array) {
for (var i=0; i<input.length; i++) {
input[i] = maskData(input[i]);
}
return input;
}
// otherwise just return itself untouched
return input;
// alternative: return an empty string
//return "";
}
If your intention is to turn multiple whitespace to a single one (as in string with multiple spaces in it-> string with multiple spaces in it), you could also use the simplified RE:
如果您打算将多个空格转换为单个空格（如string with multiple spaces in it-> string with multiple spaces in it），您还可以使用简化的 RE：
/\s+/g
A single whitespace character will be replaced by a single space. Multiple whitespace characters will also be replaced by a single space. Note that I added the gflag so the replacement occurs multiple times.
单个空格字符将被单个空格替换。多个空白字符也将被单个空格替换。请注意，我添加了g标志，因此替换发生多次。
回答by Kon
I assume inputis your input textbox or something?
我假设input是你的输入文本框还是什么？
In which case, input doesn't have a replace()function defined for it. You want to make sure you're calling replace()on a string - the value inside the input, not the input itself. Try this:
在这种情况下， input 没有replace()为其定义函数。您要确保调用replace()的是字符串 - 输入中的值，而不是输入本身。试试这个：
function maskString(input) {
return input.value.replace(/\s\s+/," ");
}
