JSFiddle - React, Tailwind, and code Playground

by Scoobler

HTML

<div class="field">
    <label for="propertyprice">Price</label>
    <input id="currency2" name="limitedtextfield" size="50" 
           type="text" class="medium" 
           maxlength="12" value="" />
    <br />
    <input type="button" id="select_option" value="select option" />   
</div>

    <div class="field">
    <label for="propertypricerange">Price Range </label>
    <select id="propertypricerange" name="propertypricerange" class="medium">
          <optgroup label="Enter Price Range">
            <option selected="selected" value="0">0    -    $100,000</option>
            <option value="100000">$100,000    -    $200,000</option>       
            <option value="200000">$200,000    -    $300,000</option>
            <option value="300000">$300,000    -    $400,000</option>
            <option value="400000">$400,000    -    $500,000</option>       
            <option value="500000">$500,000    -    $600,000</option>       
            <option value="600000">$600,000    -    $700,000</option>       
            <option value="700000">$700,000    -    $800,000</option>       
            <option value="800000">$800,000    -    $900,000</option>       
            <option value="900000">$900,000    -    $1,000,000</option>     
            <option value="1000000">$1,000,000    -    $2,000,000</option>      
            <option value="2000000">$2,000,000    -    $3,000,000</option>      
            <option value="3000000">$3,000,000    -    $4,000,000</option>      
            <option value="4000000">$4,000,000    -    $5,000,000</option>      
            <option value="5000000">$5,000,000    -    $10,000,000</option>
         </optgroup>
      </select>
</div>

JavaScript

Number.prototype.toNearest = function(num) {
    return Math.round(this/num)*num-100000; // Round up, then remove 100000
}
$("#select_option").click(function() {
    var no = $("#currency2").val()-0; // Get the typed value, and convert to a int
    $("#propertypricerange").val(no.toNearest(100000)); // Set the value of the selector.
});