回复：

我需要一个正则表达式模式到
检查
字母数字（a-zA-z0-9）的字符串，并且
还包含下划线，hypen和点

I need a regular expression pattern to check a string for alphanumeric(a-zA-z0-9) and also can contain underscore, hypen and dot

模式将是[_ a-zA-Z0-9 \\-\\。] +

请注意双反斜杠，因为这首先被解释为Java字符串，反斜杠需要保持原样不变。

Note the double-backslashes, since this is first interpreted as a Java string and the backslashes need to stay intact for the regex.