如果发现错误，则需要在单击“提交”按钮后保留文本框中的值

heartily regards from me I need to retain values in text boxes after submit button on click if found error. basically the thing I want, if user left any fields blank and press save button then error message pop up and without refreshing the page it takes back the user to the form where he just have to fill the fields that were left blank... below is my codeheartily regards from me I need to retain value