Data Annotations

Tag Helper 结合 Data Annotations 可以生成不同属性的标签及验证规则。

Data Annotations 示例：

public class StudentCreateViewModel
{
    [Display(Name = "名")]
    [Required]
    public string FirstName { get; set; }
    [Display(Name = "姓"), Required, MaxLength(10)]
    public string LastName { get; set; }
    [Display(Name = "出生日期")]
    public DateTime BirthDate { get; set; }
    [Display(Name = "性别")]
    public Gender Gender { get; set; }
}

View 中显式验证信息：

@using Tutorial.Web.Model
@model Tutorial.Web.ViewModels.StudentCreateViewModel
<h1>创建学生</h1>
<form method="post">
    <div>
        <label asp-for="FirstName"></label>
        <input asp-for="FirstName" />
        <span asp-validation-for="FirstName"></span>
    </div>
    <div>
        <label asp-for="LastName"></label>
        <input asp-for="LastName" />
        <span asp-validation-for="LastName"></span>
    </div>
    <div>
        <label asp-for="BirthDate"></label>
        <input asp-for="BirthDate" type="date" />
        <span asp-validation-for="BirthDate"></span>
    </div>
    <div>
        <label asp-for="Gender"></label>
        <select asp-for="Gender" asp-items="Html.GetEnumSelectList<Gender>()"></select>
        <span asp-validation-for="Gender"></span>
    </div>
    <div asp-validation-summary="ModelOnly"></div>
    <button type="submit" name="save">保存</button>
</form>

Controller 中读取验证信息：

[HttpPost]
[ValidateAntiForgeryToken]
public IActionResult Create(StudentCreateViewModel student)
{
    if (ModelState.IsValid)
    {
        var newStudent = new Student
        {
            FirstName = student.FirstName,
            LastName = student.LastName,
            BirthDate = student.BirthDate,
            Gender = student.Gender
        };
        var newModel = _repository.Add(newStudent);
        return RedirectToAction(nameof(Detail), new { id = newModel.Id });
    }
    ModelState.AddModelError(string.Empty, "Model Level Error!");
    return View();
}

源码

Tutorial.zip