使用MVC的Ajax.BeginForm方法实现异步验证

using System;
using System.ComponentModel.DataAnnotations;
 
namespace XHelent.Models
{
    public class Registration : IValidatableObject
    {
        
        public string RegisrationUniqueId { get; set; }
 
        [Required]
        [Display(Name = "姓名")]
        public string Name { get; set; }
 
        [Required]
        [Display(Name = "年龄")]
        public int Age { get; set; }
 
        public System.Collections.Generic.IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
        {
            if (Age < 18)
            {
                yield return new ValidationResult("年龄至少18岁以上", new String[]{"Age"});
            }
        }
    }
}
 
让model实现了IValidatableObject，在model层自定义验证逻辑和错误信息。

[HttpPost]
        public PartialViewResult Index(Registration model)
        {
            if (ModelState.IsValid)
            {
                RNGCryptoServiceProvider csp = new RNGCryptoServiceProvider();
                byte[] registrationBytes = new byte[16];
                csp.GetBytes(registrationBytes);
                model.RegisrationUniqueId = Convert.ToBase64String(registrationBytes);
                return PartialView("Success", model);
            }
            else
            {
                return PartialView("FormContent", model);
            }
        }

@model XHelent.Models.Registration
 
@{
    AjaxOptions options = new AjaxOptions
    {
        HttpMethod = "Post",
        UpdateTargetId = "formContent" //可忽略
    };
}
 
<style type="text/css">
    .field-validation-error {
        color: red;
    }
</style>
 
@using (Ajax.BeginForm(options))
{
    <fieldset>
        <legend>登记</legend>
 
        <div class="editor-label">
            @Html.LabelFor(model => model.Name)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Name)
            @Html.ValidationMessageFor(model => model.Name)
        </div>
        
        <div class="editor-label">
            @Html.LabelFor(model => model.Age)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Age)
            @Html.ValidationMessageFor(model => model.Age)
        </div>
        
        <div>
            <input type="submit" value="登记"/>
        </div>
    </fieldset>
}

Home/Success.cshmtl视图

@model XHelent.Models.Registration
 
<h2>恭喜，注册成功了！</h2>
<p>注册号为：@Model.RegisrationUniqueId</p>