与仅包含字母或字母数字的字符串匹配的正则表达式

Question

I am currently using a regular expression that accepts only alphabets, like

 ?:[a-z][a-z]+

I have also used a regular expression that accepts alphanumeric but it does not meet my requirements

My strings are in following pattern

"john" or "john123"  

Any kind of help would be appreciated

Answer 1

试试^[a-zA-Z0-9]+$ ，这个对我^[a-zA-Z0-9]+$

Answer 2

尝试使用此^([A-Za-z]|[0-9])+$

Answer 3

您可以使用(:?[a-z0-9][a-z0-9]*) ' 不捕获 '或([a-z0-9][a-z0-9]*) ' 捕获 ' 区分大小写模式以匹配字母数字单词，具体取决于您是否要捕获与正则表达式匹配的单词。

Answer 4

此正则表达式在String的开头接受字母，在末尾接受字母数字，您可以在https://regex101.com/中对其进行测试

^[A-Za-z][A-Za-z0-9]*(?:_[A-Za-z0-9]+)*$