클라이언트 측 유효성 검사 속성을 생성하지 않는 MaxLength 속성

클라이언트 측 유효성 검사 속성을 생성하지 않는 MaxLength 속성

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ASP.NET MVC3 클라이언트 측 유효성 검사에 흥미로운 문제가 있습니다. 다음과 같은 수업이 있습니다.

public class Instrument : BaseObject
{
    public int Id { get; set; }

    [Required(ErrorMessage = "Name is required.")]
    [MaxLength(40, ErrorMessage = "Name cannot be longer than 40 characters.")]
    public string Name { get; set; }
}

내 관점에서 :

<div class="editor-field">
    @Html.EditorFor(model => model.Name)
    @Html.ValidationMessageFor(model => model.Name)
</div>

이 필드의 텍스트 상자에 대해 생성 된 HTML은 다음과 같습니다.

<input class="text-box single-line" data-val="true" data-val-required="Name is required." id="Name" name="Name" type="text" value="">

의 흔적은 MaxLengthAttribute없지만 다른 모든 것이 작동하는 것 같습니다.

무슨 일이 일어나고 있는지 아이디어가 있습니까?

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[StringLength]속성을 사용해보십시오 .

[Required(ErrorMessage = "Name is required.")]
[StringLength(40, ErrorMessage = "Name cannot be longer than 40 characters.")]
public string Name { get; set; }

이는 유효성 검사 목적입니다. 예를 들어 입력에 maxlength 속성을 설정하려면 이 게시물에 표시된 대로 사용자 지정 데이터 주석 메타 데이터 공급자를 작성 하고 기본 템플릿을 사용자 지정할 수 있습니다 .

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이 문제를 해결하기 위해 jquery의 일부를 사용했습니다.

$("input[data-val-length-max]").each(function (index, element) {
   var length = parseInt($(this).attr("data-val-length-max"));
   $(this).prop("maxlength", length);
});

선택기는 data-val-length-max 속성 세트가있는 모든 요소를 ​​찾습니다. 이것은 StringLength 유효성 검사 속성이 설정할 속성입니다.

각 루프는 이러한 일치 항목을 반복하고이 속성의 값을 구문 분석하고 설정해야하는 mxlength 속성에 할당합니다.

문서 준비 기능에 이것을 추가하기 만하면됩니다.

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MaxLengthAttributeMVC 5.1 업데이트 이후 작동 중 : 변경 사항

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MVC 4에서 입력 유형 텍스트에서 maxlenght를 원하십니까? 당신은 할 수 있습니다!

@Html.TextBoxFor(model => model.Item3.ADR_ZIP, new { @class = "gui-input ui-oblig", @maxlength = "5" })

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그의 대답에 대한 @ Nick-Harrison의 소품 :

$("input[data-val-length-max]").each(function (index, element) {
var length = parseInt($(this).attr("data-val-length-max"));
$(this).prop("maxlength", length);
});

parseInt ()가 무엇인지 궁금합니다. 나는 문제없이 이것을 단순화했습니다 ...

$("input[data-val-length-max]").each(function (index, element) {
    element.setAttribute("maxlength", element.getAttribute("data-val-length-max"))
});

나는 Nicks 답변에 대해 언급했지만 아직 충분한 담당자가 없습니다.

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나는 이와 동일한 문제가 있었고 내 뷰 모델에서 IValidatableObject 인터페이스를 구현하여 해결할 수있었습니다.

public class RegisterViewModel : IValidatableObject
{
    /// <summary>
    /// Error message for Minimum password
    /// </summary>
    public static string PasswordLengthErrorMessage => $"The password must be at least {PasswordMinimumLength} characters";

    /// <summary>
    /// Minimum acceptable password length
    /// </summary>
    public const int PasswordMinimumLength = 8;

    /// <summary>
    /// Gets or sets the password provided by the user.
    /// </summary>
    [Required]
    [DataType(DataType.Password)]
    [Display(Name = "Password")]
    public string Password { get; set; }

    /// <summary>
    /// Only need to validate the minimum length
    /// </summary>
    /// <param name="validationContext">ValidationContext, ignored</param>
    /// <returns>List of validation errors</returns>
    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        var errorList = new List<ValidationResult>();
        if ((Password?.Length ?? 0 ) < PasswordMinimumLength)
        {
            errorList.Add(new ValidationResult(PasswordLengthErrorMessage, new List<string>() {"Password"}));
        }
        return errorList;
    }
}

The markup in the Razor is then...

<div class="form-group">
    @Html.LabelFor(m => m.Password)
    @Html.PasswordFor(m => m.Password, new { @class = "form-control input-lg" }
    <div class="password-helper">Must contain: 8 characters, 1 upper-case, 1 lower-case
    </div>
    @Html.ValidationMessagesFor(m => m.Password, new { @class = "text-danger" })
</div>

This works really well. If I attempt to use [StringLength] instead then the rendered HTML is just not correct. The validation should render as:

<span class="text-danger field-validation-invalid field-validation-error" data-valmsg-for="Password" data-valmsg-replace="true"><span id="Password-error" class="">The Password should be a minimum of 8 characters long.</span></span>

With the StringLengthAttribute the rendered HTML shows as a ValidationSummary which is not correct. The funny thing is that when the validator fails the submit is still blocked!

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StringLength works great, i used it this way:

[StringLength(25,MinimumLength=1,ErrorMessage="Sorry only 25 characters allowed for 
              ProductName")]
public string ProductName { get; set; }

or Just Use RegularExpression without StringLength:

[RegularExpression(@"^[a-zA-Z0-9'@&#.\s]{1,25}$", ErrorMessage = "Reg Says Sorry only 25 
                   characters allowed for ProductName")]    
public string ProductName { get; set; }

but for me above methods gave error in display view, cause i had already ProductName field in database which had more than 25 characters

so finally i came across this and this post and tried to validate without model like this:

 <div class="editor-field">
 @Html.TextBoxFor(model => model.ProductName, new
 {
 @class = "form-control",
 data_val = "true",
 data_val_length = "Sorry only 25 characters allowed for ProductName",
 data_val_length_max = "25",
 data_val_length_min = "1"
 })
 <span class="validation"> @Html.ValidationMessageFor(model => model.ProductName)</span>
 </div>

this solved my issue, you can also do validation manually using jquery or using ModelState.AddModelError

hope helps someone.

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I know I am very late to the party, but I finaly found out how we can register the MaxLengthAttribute.

First we need a validator:

public class MaxLengthClientValidator : DataAnnotationsModelValidator<MaxLengthAttribute>
{
    private readonly string _errorMessage;
    private readonly int _length;


    public MaxLengthClientValidator(ModelMetadata metadata, ControllerContext context, MaxLengthAttribute attribute)
    : base(metadata, context, attribute)
    {
        _errorMessage = attribute.FormatErrorMessage(metadata.DisplayName);
        _length = attribute.Length;
    }

    public override IEnumerable<ModelClientValidationRule> GetClientValidationRules()
    {
        var rule = new ModelClientValidationRule
        {
            ErrorMessage = _errorMessage,
            ValidationType = "length"
        };

        rule.ValidationParameters["max"] = _length;
        yield return rule;
    }
}

Nothing realy special. In the constructor we save some values from the attribute. In the GetClientValidationRules we set a rule. ValidationType = "length" is mapped to data-val-length by the framework. rule.ValidationParameters["max"] is for the data-val-length-max attribute.

Now since you have a validator, you only need to register it in global.asax:

protected void Application_Start()
{
    //...

    //Register Validator
    DataAnnotationsModelValidatorProvider.RegisterAdapter(typeof(MaxLengthAttribute), typeof(MaxLengthClientValidator));
}

Et voila, it just works.

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I tried this for all the inputs in my html document(textarea,inputs,etc) that had the data-val-length-max property and it works correctly.

$(document).ready(function () {
    $(":input[data-val-length-max]").each(function (index, element) {
        var length = parseInt($(this).attr("data-val-length-max"));
        $(this).prop("maxlength", length);
    });
});

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This can replace the MaxLength and the MinLength

[StringLength(40, MinimumLength = 10 , ErrorMessage = "Name cannot be longer than 40 characters and less than 10")]

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<input class="text-box single-line" data-val="true" data-val-required="Name is required." 
    id="Name1" name="Name" type="text" value="">

$('#Name1').keypress(function () {
    if (this.value.length >= 5) return false;
});

참고URL : https://stackoverflow.com/questions/6801656/maxlength-attribute-not-generating-client-side-validation-attributes