javascript 注册。表达式检查字符串的第一个字母
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Reg. Expression checks first letter of a string
提问by Aadi
I would like to check if the first character of a string is a letter or not. My regular expression is:
我想检查字符串的第一个字符是否是字母。我的正则表达式是：
'/^([a-zA-Z.*])$/'
This is not working. What's wrong with it?
这是行不通的。它出什么问题了？
采纳答案by Peter C
Try the following:
请尝试以下操作：
'/^[a-zA-Z].*$/'
which checks if the first letter is in the alphabet and allows any character after that.
它检查第一个字母是否在字母表中并允许其后的任何字符。
回答by Dimitry
Your expression does not need .* nor should it have the $
你的表达式不需要 .* 也不应该有 $
'/^([a-zA-Z])/'
In fact, if you don't need to know what this letter is, you could go even simpler:
事实上，如果你不需要知道这封信是什么，你可以更简单：
'/^[a-zA-Z]/'
// These expressions are true
/^[a-zA-Z]/.test("Sample text")
var re = new RegExp('^[a-zA-Z]');
re.test('Sample text');
