Javascript 未捕获的类型错误：无法读取 Jquery 中未定义的属性“修剪”
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Uncaught TypeError: Cannot read property 'trim' of undefined in Jquery
提问by Saravanan Arunagiri
In Jquery replace the space character to '%20'. but working in other forms not in single form. in consists header as
在 Jquery 中，将空格字符替换为 '%20'。但以其他形式而不是单一形式工作。在包含标题为
<header>
<script src="http://code.jquery.com/jquery-1.9.1.js"></script>
<script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script>
<link rel="stylesheet" href="http://code.jquery.com/ui/1.10.3/themes/smoothness/jquery-ui.css" />
</header>
the code using in other form its working well.
以其他形式使用的代码运行良好。
var vname = $("#EarningsTypes").val();
vname = vname.trim().replace(/ /g, '%20');
jQuery.noConflict();
回答by Tushar
You're getting error
你得到错误
Uncaught TypeError: Cannot read property 'trim' of undefined in Jquery
未捕获的类型错误：无法读取 Jquery 中未定义的属性“修剪”
that means, the variable vnameis undefined. To prevent this error from occurring, you can use the ternary operator to set the default value of the string to empty string when it is undefined.
这意味着，变量vname是undefined。为防止出现此错误，可以使用三元运算符将字符串的默认值设置为空字符串时undefined。
var vname = $("#EarningsTypes").val() == undefined ? '' : $("#EarningsTypes").val().trim();
vname = vname.replace(/ /g, '%20');
You can also use ||to set the default value
也可以使用||来设置默认值
var vname = $("#EarningsTypes").val() || '';
If you're using an older browser that doesn't support trim, you can use polyfill from MDN
如果您使用的是不支持 的旧浏览器，则trim可以使用MDN 中的 polyfill
if (!String.prototype.trim) {
String.prototype.trim = function() {
return this.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
};
}
