i have used class='required'
for required validation which is working fine when i remove onClick="this.form.submit(); this.disabled=true;
from submit button.
i want to disable multi click with validation
<form action="<?php echo $this->url('weeklyplan', array('action' => 'add')); ?>" method="post" id='myform'>
<div class="mainformdiv">
<div class= "formelementblock">
<div class="formelement">
<select name="txtdefined_week_id" id="txtdefined_week_id" class="select-block required" onchange="showdateranges()">
<option value="">Select Defined Week</option>
<?php foreach ($definedweeks as $obj) { ?>
<option value="<?php echo $obj->defined_week_id; ?>"><?php echo $obj->start_day . "-" . $obj->end_day; ?></option>
<?php } ?>
</select>
</div>
</div>
<div class= "formelementblock">
<div class="formelement">
<input type="text" readonly="readonly" name="txtstart_date" class="input-text datepickerwidth required" id="txtstart_date" placeholder="Start Date*"/>
</div>
</div>
<div class= "formelementblock last">
<div class="formelement">
<input type="text" readonly="readonly" name="txtend_date" class="input-text datepickerwidth required" id="txtend_date" placeholder="End Date*"/>
</div>
</div>
</div>
<div class="clear"></div>
<div class="form-button">
<div class="button-block">
<input onClick="this.form.submit(); this.disabled=true;" class="button" type="submit" name="button" id="button" value="Save" />
<input class="button" type="button" name="button" id="button" value="Cancel" onclick="window.location = '<?php echo $this->url('weeklyplan', array('action' => 'index')); ?>'" />
</div>
</div>
</form>