I have a function for a registration page where if the data required isn't entered by the user then it alerts the user to fill it in. The form still submits the information though so not sure what I'm doing wrong. I want it to not submit until all data is submitted and correct.
function checkdetails()
{
if (document.form1.txtname.value == "")
{alert("Please fiill in your forename.");
}
if (document.form1.txtsurname.value == "")
{alert("Please fill in your surname.");
}
if (document.form1.txtusername == "")
{alert("Please create a username.");
}
if (document.form1.DOBDay.selectedIndex == 0)
{alert("Please select the day you were born.");
}
if (document.form1.DOBMonth.selectedIndex == 0)
{ alert("Please select the month you were born");
}
if (document.form1.DOBYear.selectedIndex == 0)
{alert("Please fill in the year you were born.");
}
if (document.form1.txtemail.value == "")
{alert("Please enter your e-mail address.");
}
if (document.form1.terms.checked == false)
{alert("Please tick that you have read the Terms and Conditions.");
}
}
<form action="Home.html" method="post" name="form1" onsubmit="Display()">
<table bgcolor="white" width="700" border="0" align="center">
<col width="200">
<col width="200">
<tr>
<th colspan = "2" align = "center" bgcolor="grey"> Fill the form to sign up. </th>
</tr>
<tr>
<td> </td>
</tr>
<tr>
<td colspan="2" style="font-size:12px">Fields marked with * are mandatory</td>
</tr>
<tr>
<td> </td>
</tr>
<tr>
<td>Forename*</td>
<td>Surname*</td>
</tr>
<tr>
<td><label>
<input type="text" name="txtname" id="txtname" class="info" />
<td><label>
<input type="text" name="txtsurname" id="txtsurname" class="info" />
</label></td>
</tr>
<tr>
<td> Create Username*</td>
<td> Birthday</td>
</tr>
<tr>
<td><label>
<input type="text" name="txtusername" id="txtusername" class="info"/>
</label></td>
<td><select name="DOBMonth">
<option> Month </option>
<option value="January">January</option>
<option value="Febuary">Febuary</option>
<option value="March">March</option>
<option value="April">April</option>
<option value="May">May</option>
<option value="June">June</option>
<option value="July">July</option>
<option value="August">August</option>
<option value="September">September</option>
<option value="October">October</option>
<option value="November">November</option>
<option value="December">December</option>
</select>
<select name="DOBDay">
<option> Day </option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
<option value="7">7</option>
<option value="8">8</option>
<option value="9">9</option>
<option value="10">10</option>
<option value="11">11</option>
<option value="12">12</option>
<option value="13">13</option>
<option value="14">14</option>
<option value="15">15</option>
<option value="16">16</option>
<option value="17">17</option>
<option value="18">18</option>
<option value="19">19</option>
<option value="20">20</option>
<option value="21">21</option>
<option value="22">22</option>
<option value="23">23</option>
<option value="24">24</option>
<option value="25">25</option>
<option value="26">26</option>
<option value="27">27</option>
<option value="28">28</option>
<option value="29">29</option>
<option value="30">30</option>
<option value="31">31</option>
</select>
<select name="DOBYear">
<option> Year </option>
<option value="2016">2016</option>
<option value="2015">2015</option>
<option value="2014">2014</option>
<option value="2013">2013</option>
<option value="2012">2012</option>
<option value="2011">2011</option>
<option value="2010">2010</option>
<option value="2009">2009</option>
<option value="2008">2008</option>
<option value="2007">2007</option>
<option value="2006">2006</option>
<option value="2005">2005</option>
<option value="2004">2004</option>
<option value="2003">2003</option>
<option value="2002">2002</option>
<option value="2001">2001</option>
<option value="2000">2000</option>
<option value="1999">1998</option>
<option value="1998">1998</option>
<option value="1997">1997</option>
<option value="1996">1996</option>
<option value="1995">1995</option>
<option value="1994">1994</option>
<option value="1993">1993</option>
<option value="1992">1992</option>
<option value="1991">1991</option>
<option value="1990">1990</option>
<option value="1989">1989</option>
<option value="1988">1988</option>
<option value="1987">1987</option>
<option value="1986">1986</option>
<option value="1985">1985</option>
<option value="1984">1984</option>
<option value="1983">1983</option>
<option value="1982">1982</option>
<option value="1981">1981</option>
<option value="1980">1980</option>
<option value="1979">1979</option>
<option value="1978">1978</option>
<option value="1977">1977</option>
<option value="1976">1976</option>
<option value="1975">1975</option>
<option value="1974">1974</option>
<option value="1973">1973</option>
<option value="1972">1972</option>
<option value="1971">1971</option>
<option value="1970">1970</option>
<option value="1969">1969</option>
<option value="1968">1968</option>
<option value="1967">1967</option>
<option value="1966">1966</option>
<option value="1965">1965</option>
<option value="1964">1964</option>
<option value="1963">1963</option>
<option value="1962">1962</option>
<option value="1961">1961</option>
<option value="1960">1960</option>
<option value="1959">1959</option>
<option value="1958">1958</option>
<option value="1957">1957</option>
<option value="1956">1956</option>
<option value="1955">1955</option>
<option value="1954">1954</option>
<option value="1953">1953</option>
<option value="1952">1952</option>
<option value="1951">1951</option>
<option value="1950">1950</option>
<option value="1949">1949</option>
<option value="1948">1948</option>
<option value="1947">1947</option>
</select>
<tr>
<td>Email*</td>
<td>Confirm Email*</td>
</tr>
<tr>
<td><label>
<input type="text" name="txtemail" id="txtemail" class="info" onchange="ValidateEmail(txtemail)" />
<td><label>
<input type="text" name="txtemail2" id="txtemail2" class="info" onchange="ValidateEmail2(txtemail2)"/>
</label></td>
</tr>
<tr>
<td>Password*</td>
<td>Confirm Pasword*</td>
</tr>
<tr>
<td><label>
<input type="password" name="txtpassword" id="txtpassword" class="info"/>
<td><label>
<input type="password" name="txtpassword2" id="txtpassword2" class="info"/>
</label></td>
</tr>
<td colspan="2" style="font-size:12px">**Passwords must be at least 8 characters in lenght.</td>
</tr>
<tr>
<td> </td>
</tr>
<tr>
<td colspan="2">
<label>
<input type="checkbox" name="terms" value="terms" id="terms" />
I agree to the Terms and Conditions</label>
</td></tr>
<br><br><br>
<tr>
<td colspan="2"><label>
<input type="checkbox" name="notify" value="notify" id="notify" />
I want to receive notifications by text/email about new products in stock.</label>
</td>
</tr>
<tr>
<td> </td>
</tr>
<tr>
<td><label>
<input type="submit" name="Login" id="Login" value="Login" onclick="checkdetails()" />
</label></td>
<td><label>
<input type="reset" name="Reset" id="Reset" value="Reset" />
</label></td>
</tr>
<tr>
<td> </td>
</tr>
</table>
</form>
it's better to use html5 attribute required !
<input type="text" name="input" required >