如何获得MVC3模型验证的真或假输出
本文关键字:输出 验证 何获得 MVC3 模型 | 更新日期: 2023-09-27 18:12:35
我使用一个表单来发布信息,我的模型内置了验证。我知道我可以通过使用以下任意一个来验证字段:
@Html.ValidationSummary() //To validate all fields
@Html.ValidationMessageFor(x => x.FirstName) //To validate single field
这两个方法都只是返回一个HTML列表(For ValidationSummary)或一个span (ValidateionMessageFor)。
我想做的是得到一个真或假的声明,如果字段是有效的或不(或null,如果没有),这样我就可以做一些自定义的样式框,包含输入,甚至标签为它。
有没有人知道是否有这样的代码可以做到这一点,比如@Html.IsValid(x => x.FirstName)
模型:
using System.ComponentModel.DataAnnotations;
namespace X.Web.Helpers
{
public class RequestSamplesModel
{
[Required]
public string FirstName { get; set; }
[Required]
public string LastName { get; set; }
public string Email { get; set; }
[Required]
public string Line1 { get; set; }
[Required]
public string Line2 { get; set; }
[Required]
public string City { get; set; }
[Required]
public string Postcode { get; set; }
[Required]
public string Country { get; set; }
}
}
视图:
@{
Layout = "~/Views/Shared/_PlainLayout.cshtml";
}
@using X.Web.Helpers
@model RequestSamplesModel
<form action="/Site/RequestSamples" method="POST">
<div class="form-item">
<span>First Name:</span>@Html.TextBoxFor(x => x.FirstName)</div>
<div class="form-item">
<span>Last Name:</span>@Html.TextBoxFor(x => x.LastName)</div>
<div class="form-item">
<span>Email:</span>@Html.TextBoxFor(x => x.Email)</div>
<div class="form-item">
<span>Address 1:</span>@Html.TextBoxFor(x => x.Line1)</div>
<div class="form-item">
<span>Address 2:</span>@Html.TextBoxFor(x => x.Line2)</div>
<div class="form-item">
<span>City:</span>@Html.TextBoxFor(x => x.City)</div>
<div class="form-item">
<span>Postcode:</span>@Html.TextBoxFor(x => x.Postcode)</div>
<div class="form-item">
<span>Country:</span>@Html.TextBoxFor(x => x.Country)</div>
<div class="form-item">
<input class="submit-button" type="image" src="/_content/images/email-submit.gif" /></div>
</form>
有谁知道是否有这样的代码可以做到这一点,比如@Html。IsValid(x => x. firstname)
不,没有这样的内置代码。但是,如果再写一个,就很简单了,现在有:
public static class HtmlExtensions
{
public static bool IsValid<TModel, TProperty>(
this HtmlHelper<TModel> htmlHelper,
Expression<Func<TModel, TProperty>> expression
)
{
var modelState = htmlHelper.ViewData.ModelState;
var name = ExpressionHelper.GetExpressionText(expression);
var key = htmlHelper.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName(name);
ModelState value;
return !modelState.TryGetValue(key, out value) ||
value.Errors.Count == 0;
}
}
现在,在您的视图中,只需将扩展方法引入范围和:
@if (Html.IsValid(x => x.FirstName))
{
@:<div>Super, the first name is valid</div>
}