How to determine whether the email is legal in java
java判断邮箱是否合法的方法：可以使用正则表达式来判断。具体代码为【boolean b=matcher.matches();if (b) {System.out.println(mail+"有效的邮箱地址！");】。
java判断邮箱是否合法的方法：
【相关学习推荐：java课程】
使用了正则表达式来进行判断，代码实现如下：
public class Test {
public static void main(String[] args) {
//电子邮件
String check = "^([a-z0-9A-Z]+[-|\\.]?)+[a-z0-9A-Z]@([a-z0-9A-Z]+(-[a-z0-9A-Z]+)?\\.)+[a-zA-Z]{2,}$";
Pattern regex = Pattern.compile(check);
Matcher matcher = regex.matcher("dffdfdf@qq.com");
boolean isMatched = matcher.matches();
System.out.println(isMatched);
}
public static void main(String[] args) {
Scanner scanner=new Scanner(System.in);
String mail=null;
System.out.println("请输入E-Mail：");
mail=scanner.next();
Pattern pattern=Pattern.compile("\\w+@(\\w+.)+[a-z]{2,3}");//\w表示a-z，A-Z，0-9(\\转义符)
Matcher matcher=pattern.matcher(mail);
boolean b=matcher.matches();
if (b) {
System.out.println(mail+"有效的邮箱地址！");
}else {
System.out.println(mail+"的格式错误！！");
}
}javascript电子邮箱的合法性验证
/**
*
*/
function isEmail(email)
{
var srt=/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/;
if(srt.test(email))
{
//不合法时
return false;
}
else
{
//合法时
return true;
}
}
}
public static boolean validateEmail(String email) {
boolean flag = false;
int pos = email.indexOf("@");
if (pos == -1 || pos == 0 || pos == email.length() - 1) {
return false;
}
String[] strings = email.split("@");
if (strings.length != 2) {// 如果邮箱不是xxx@xxx格式
return false;
}
CharSequence cs = strings[0];
for (int i = 0; i < cs.length(); i++) {
char c = cs.charAt(i);
if (!Character.isLetter(c) && !Character.isDigit(c)) {
return false;
}
}
pos = strings[1].indexOf(".");// 如果@后面没有.，则是错误的邮箱。
if (pos == -1 || pos == 0 || pos == email.length() - 1) {
return false;
}
strings = strings[1].split(".");
for (int j = 0; j < strings.length; j++) {
cs = strings[j];
if (cs.length() == 0) {
return false;
}
for (int i = 0; i < cs.length(); i++) {//如果保护不规则的字符，表示错误
char c = cs.charAt(i);
if (!Character.isLetter(c) && !Character.isDigit(c)) {
return false;
}
}
}
return true;The above is the detailed content of How to determine whether the email is legal in java. For more information, please follow other related articles on the PHP Chinese website!
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