Question

I want to display alert message and then refresh the page.

But it take infinite loop of alert messages.

   if(isValid){
      alert("alert some text");
      document.location.reload(true);
   }
   else {
       .............
   }

How can I do that with out infinite loop

Answer 1

You would have to pass along the state. Possibly refreshing the page by pointing itself with a querystring variable. Then read that variable

if (getParameterByName("reloaded") != "yes") {
    alert("username or password are incorrect");       
    window.location = 'mypage.html?reloaded=yes';  
} else {
    // Do something else..
} 

Note the getParameterByName function is found at another stackoverflow answer: How can I get query string values in JavaScript?. You could alternatively use a library such as jQuery for a better solution.