The Form component allows you to add/remove items and specify item visibility at runtime. The Form only updates the affected items and does not re-render the entire form.
In this demo, the "Show Address" checkbox specifies the visibility of address-related fields. Review the component's code to see how to set the "HomeAddress" group's visible attribute.
Click the "Add phone" button to add a new phone editor. This action adds a new item to the items array of the "phones" group. Each phone editor contains a button that deletes it from the items array and the Form.
@using DevExtreme.MVC.Demos.ViewModels
@model DynamicFormViewModel
<div class="long-title"><h3>Personal details</h3></div>
<div id="form-container">
@(Html.DevExtreme().Form<DynamicFormViewModel>()
.ID("form")
.ColCount(2)
.Items(groups => {
groups.AddGroup()
.Items(leftGroup => {
leftGroup.AddGroup()
.Caption("Personal Data")
.Items(items => {
items.AddSimpleFor(m => m.FirstName);
items.AddSimpleFor(m => m.LastName);
items.AddSimple()
.Label(l => l.Text(""))
.Editor(e =>
e.CheckBox()
.OnValueChanged("onCheckBoxValueChanged")
.Text("Show Address")
.Value(true)
);
});
leftGroup.AddGroup()
.Items(addressGroup => {
addressGroup.AddGroup()
.Name("HomeAddress")
.Caption("Home Address")
.Items(items => {
items.AddSimpleFor(m => m.Address);
items.AddSimpleFor(m => m.City);
});
});
});
groups.AddGroup()
.Name("phones-container")
.Caption("Phones")
.Items(rightGroup => {
rightGroup.AddGroup()
.Name("phones")
.Items(items => {
items.AddSimpleFor(m => m.Phones[0])
.Label(l => l.Text("Phone 1"))
.CssClass("phone-editor")
.Editor(e =>
e.TextBox()
.Mask("+1 (X00) 000-0000")
.InputAttr("aria-label", "Mask")
.MaskRules(new { X = new JS("/[01-9]/") })
.Buttons(b =>
b.Add().Name("Trash")
.Location(TextEditorButtonLocation.After)
.Widget(w =>
w.Button()
.StylingMode(ButtonStylingMode.Text)
.Icon("trash")
.OnClick("function(e) {onTrashButtonClick(0)}")
)
)
);
items.AddSimpleFor(m => m.Phones[1])
.Label(l => l.Text("Phone 2"))
.CssClass("phone-editor")
.Editor(e =>
e.TextBox()
.Mask("+1 (X00) 000-0000")
.InputAttr("aria-label", "Mask")
.MaskRules(new { X = new JS("/[01-9]/") })
.Buttons(b =>
b.Add().Name("Trash")
.Location(TextEditorButtonLocation.After)
.Widget(w =>
w.Button()
.StylingMode(ButtonStylingMode.Text)
.Icon("trash")
.OnClick("function(e) {onTrashButtonClick(1)}")
)
)
);
});
rightGroup.AddGroup()
.Items(items => {
items.AddButton()
.HorizontalAlignment(HorizontalAlignment.Left)
.CssClass("add-phone-button")
.ButtonOptions(b =>
b.Icon("add")
.Text("Add phone")
.OnClick("onAddButtonClick")
);
});
});
})
.OnInitialized("onFormInitialized")
.OnContentReady("onFormReady")
.FormData(Model)
)
</div>
<script>
var form,
employee,
isFirstLoad = true;
function onFormInitialized(e) {
form = e.component;
}
function onFormReady(e) {
if (isFirstLoad) {
employee = e.component.option("formData");
isFirstLoad = false;
}
}
function onCheckBoxValueChanged(e) {
form.itemOption("HomeAddress", "visible", e.value);
}
function onAddButtonClick() {
employee.Phones.push("");
form.itemOption("phones-container.phones", "items", getPhonesOptions(employee.Phones));
}
function onTrashButtonClick(index) {
employee.Phones.splice(index, 1);
form.itemOption("phones-container.phones", "items", getPhonesOptions(employee.Phones));
}
function getPhonesOptions(phones) {
var options = [];
for (var i = 0; i < phones.length; i++) {
options.push(generateNewPhoneOptions(i));
}
return options;
}
function generateNewPhoneOptions(index) {
return {
dataField: "Phones[" + index + "]",
editorType: "dxTextBox",
cssClass: "phone-editor",
label: {
text: "Phone " + (index + 1)
},
editorOptions: {
mask: "+1 (X00) 000-0000",
maskRules: { "X": /[01-9]/ },
buttons: [{
name: "trash",
location: "after",
options: {
stylingMode: "text",
icon: "trash",
onClick: function () {
onTrashButtonClick(index);
}
}
}]
}
}
}
</script>
using DevExtreme.AspNet.Data;
using DevExtreme.AspNet.Mvc;
using DevExtreme.MVC.Demos.Models.SampleData;
using DevExtreme.MVC.Demos.ViewModels;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Web.Mvc;
namespace DevExtreme.MVC.Demos.Controllers {
public class FormController : Controller {
public ActionResult UpdateItemsDynamically() {
return View(new DynamicFormViewModel {
FirstName = "John",
LastName = "Heart",
Address = "351 S Hill St., Los Angeles, CA",
City = "Atlanta",
Phones = new List<string> { "8005552797", "8005953232" }
});
}
}
}#form-container {
margin: 10px 10px 30px;
}
.long-title h3 {
font-family: 'Segoe UI Light', 'Helvetica Neue Light', 'Segoe UI', 'Helvetica Neue', 'Trebuchet MS', Verdana;
font-weight: 200;
font-size: 28px;
text-align: center;
margin-bottom: 20px;
}
.add-phone-button {
margin-top: 10px;
}