Edit file File name : add-new-ad.js Content :$(document).ready(function () { $("#district").change(function () { var district = this.value; $('#city').empty(); $.ajax({ url: "post-and-get/ajax/add-new-ad.php", type: "POST", data: { district: district, actiongetSUB: 'GETSUBCITY' }, dataType: "JSON", success: function (jsonStr) { var html = '<option value=""> -- City -- </option>'; $.each(jsonStr, function (key, data) { html += '<option value="' + data.id + '">' + data.name + '</option>'; }); $('#city').append(html); } }); }); $("#category").change(function () { var category = this.value; $('#subCategory').empty(); $.ajax({ url: "post-and-get/ajax/add-new-ad.php", type: "POST", data: { category: category, actiongetSubCategory: 'GETSUBCATEGORY' }, dataType: "JSON", success: function (jsonStr) { var html = '<option value=""> -- Sub Category -- </option>'; $.each(jsonStr, function (key, data) { html += '<option value="' + data.id + '">' + data.name + '</option>'; }); $('#subCategory').append(html); } }); }); $("#subCategory").change(function () { var subCategory = this.value; $('#brand').empty(); $.ajax({ url: "post-and-get/ajax/add-new-ad.php", type: "POST", data: { subCategory: subCategory, actiongetBrand: 'actiongetBrand' }, dataType: "JSON", success: function (jsonStr) { var html = '<option value=""> -- Select Brand -- </option>'; $.each(jsonStr, function (key, data) { html += '<option value="' + data.id + '">' + data.name + '</option>'; }); $('#brand').append(html); } }); }); });Save