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JavaScript help (part of form validation)?

  • Hi and thank you in advance for helping me and giving me your tips. I am learning javascript and i just got to the form validation point in the book i have. Anyways here is the problem i have and here is the code: When the user doesn't put anything in the Username field and just leaves it blank on the form submit javascript should check that username field and make sure it is NOT blank, if it is blank it is to write a message next to the Username field. It does everything perfectly except for the last step, it writes the certain error description next to the Username field but it disappears after a second. I think it has to do witht he page RELOADING and clearing all fields in the form. Code ========== <head> <!-- Validate login script --> <script language="javascript" type="text/javascript"> <!-- var whiteSpace = " \t\n\r"; var errorTipInsertSpot; var errorTip; function isEmpty(s) { var i; if((s == null) || (s.length == 0)) return true; // Search string looking for characters that are not whitespace for (i = 0; i < s.length; i++) { var c = s.charAt(i); if (whiteSpace.indexOf(c) == -1) return false; } // All characters are whitespace. return true; } function validate() { if (isEmpty(document.signIn.username.value)… { errorTipInsertSpot = document.getElementById('usernameError')… errorTip = document.createTextNode("Username can't be empty"); errorTipInsertSpot.setAttribute('cla… 'formError') errorTipInsertSpot.appendChild(error… } } //--> </script> </head> <body> ..... <table border="0" cellspacing="0" cellpadding="0"> <form action="" method="post" name="signIn" id="signIn" onsubmit="return validate()"> <tr> <td width="26"></td> <td width="136">Username:</td> <td width="130"><input name="username" type="text" id="username" size="15" maxlength="25" /></td> <td width="130"><div id="usernameError"> </div></td> </tr> .... ========== I left most of the XHTML and code out because it is not needed. Anyways i havent finished the part of the code that tells the user if the form field has information that will pass. So my form javascript isn't complete BUT that part of the code i have should function perfectly, the only stuff i left out was email & password check. Thanks again for helping me, Jason

  • Answer:

    In your function validate() INSIDE your if statement return false if(isEmpty(whatever)) { //do some stuff return false; //this won't let the form to trigger the action }

Jason at Yahoo! Answers Visit the source

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