document.write('<p>&nbsp;解析：</p><div>function CheckMail($mailaddress){</div><div>if(eregi(\'^[a-zA-Z0-9_-.]+@[a-zA-Z0-9-]+.[a-zA-Z0-9-.]+$\',</div><div>&nbsp;$mailaddress)){</div><div>&nbsp;return true;</div><div>}else{</div><div>&nbsp;return false;</div><div>}</div><div>}</div><div>对于正则的解释：</div><div>^[a-zA-Z0-9_-.] 是至少由一个字符、数字、下画线、连字符、点为开始的字</div><div>符串；$ 更多。</div>');