JavaScript checks whether the E-mail address is legal, and uses javascripte-mail

JavaScript checks whether the E-mail address is legal, and uses javascripte-mail

<Span style = "font-family: Arial, Helvetica, sans-serif; background-color: rgb (255,255,255);"> compile the custom JavaScript function checkEmail (), in this function, first determine whether the E-mail text box is empty, and then apply the regular expression to determine whether the E-mail address is legal. If it is invalid, the system prompts the user </span>

<Span style = "font-family: Arial, Helvetica, sans-serif; background-color: rgb (255,255,255 ); "> </span> <pre name =" code "class =" javascript "> <script type =" text/javascript "> function checkEmail () {var email = document. getElementById ("email"); if (email. value = null | email. value = "") {alert ("Enter the email address! "); Email. focus (); return;} var regExp =/\ w + ([-+.] \ w +) * @ \ w + ([-.] \ w + )*\. \ w + ([-.] \ w +) */; if (! RegExp. test (email. value) {alert ("the email address you entered is incorrect! "); Email. focus (); return ;}</script> <span style =" white-space: pre "> </span>