如何为Asp.NET Core 3.0的自定义RequiredIf属性设置客户端验证

如何解决如何为Asp.NET Core 3.0的自定义RequiredIf属性设置客户端验证

根据各种来源设置验证后，我无法启动客户端验证方法。经过大量的努力，我发现更改脚本加载时间的顺序解决了该问题。我提供了一个答案来显示asp.net core 3.0 MVC的'RequiredIf'自定义属性的完整设置。希望它将节省其他人的宝贵时间。

解决方法

新建一个继承ValidationAttribute和IClientModelValidator的类：

buildscript {
    
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:4.0.1'
        classpath 'com.google.firebase:perf-plugin:1.3.1'
        classpath 'com.google.gms:google-services:4.3.3'
        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.1.1'
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        maven { url 'https://jitpack.io' }
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

将模型中的属性应用为属性上方的注释：

    public class RequiredIfAttribute : ValidationAttribute,IClientModelValidator
    {
        private string PropertyName { get; set; }

        private object DesiredValue { get; set; }

        public RequiredIfAttribute(string propertyName,object desiredvalue)
        {
            PropertyName = propertyName;
            DesiredValue = desiredvalue;
        }

        protected override ValidationResult IsValid(object value,ValidationContext context)
        {
            object instance = context.ObjectInstance;
            Type type = instance.GetType();
            object propertyvalue = type.GetProperty(PropertyName).GetValue(instance,null);

            if ((value == null && propertyvalue == DesiredValue) || (value == null && propertyvalue != null && propertyvalue.Equals(DesiredValue)))
            {
                return new ValidationResult(ErrorMessage);
            }

            return ValidationResult.Success;
        }

        public void AddValidation(ClientModelValidationContext context)
        {
            MergeAttribute(context.Attributes,"data-val","true");
            var errorMessage = FormatErrorMessage(context.ModelMetadata.GetDisplayName());
            MergeAttribute(context.Attributes,"data-val-requiredif",errorMessage);
            MergeAttribute(context.Attributes,"data-val-requiredif-otherproperty",PropertyName);
            MergeAttribute(context.Attributes,"data-val-requiredif-otherpropertyvalue",DesiredValue == null? "": DesiredValue.ToString());
        }

        private bool MergeAttribute(IDictionary<string,string> attributes,string key,string value)
        {
            if (attributes.ContainsKey(key))
            {
                return false;
            }
            attributes.Add(key,value);
            return true;
        }
    }
}

将验证元素添加到您的html中：

[Display(Name = "Effective Date Column Name")]
[RequiredIf("EffectiveDate",null,ErrorMessage = "Effective Date Column Name is required or Enter an Effective Date.")]
public string ColumnNameEffectiveDate { get; set; }

[Display(Name = "Enter Effective Date")]
public DateTime? EffectiveDate { get; set; }

在运行时，HTML将更改为包括验证标签：

<fieldset>
    <legend class="w-auto">Step 4: Set Effective Date</legend>
    <div class="form-row">
        <div class="form-group col-12">
            <small class="form-text">Select the name of the date column to import,or enter a date.</small>
        </div>
        <div class="form-group col-12 col-lg-4 columnheader">
            <label asp-for="@Model.ColumnNameEffectiveDate" class="slightlyBold"></label>
            <select class="form-control selectpicker"
                    asp-for="@Model.ColumnNameEffectiveDate">
                <option value="">Nothing selected</option>
            </select>
            <span asp-validation-for="@Model.ColumnNameEffectiveDate" class="text-danger"></span> <==== HERE
        </div>
        <div class="form-group col-12 col-lg-2 text-center">
            <label class="slightlyBold pt-4">OR</label>
        </div>
        <div class="form-group col-12 col-lg-4">
            <label asp-for="@Model.EffectiveDate" class="slightlyBold">Enter Effective Date:</label>
            <input type="text" class="datepicker form-control" asp-for="@Model.EffectiveDate">
        </div>
    </div>
</fieldset>

制作一个将新规则添加到不干扰适配器的javascript文件（我将我的文件称为“ customValidationRules.js”）：

<select class="form-control selectpicker" data-val="true" data-val-requiredif="Effective Date Column Name is required or Enter an Effective Date." data-val-requiredif-otherproperty="EffectiveDate" data-val-requiredif-otherpropertyvalue="" id="ColumnNameEffectiveDate" name="ColumnNameEffectiveDate" disabled="disabled">
    <option value="">Nothing selected</option>
</select>

以及该规则要运行的方法的第二个文件（我将我的文件称为“ customValidationMethods.js”）：

$(function () {

    jQuery.validator.unobtrusive.adapters.add("requiredif",["otherproperty","otherpropertyvalue"],function (options) {
            options.rules["requiredif"] = options.params;
            options.messages["requiredif"] = options.message
        });

}(jQuery));

确保引用该页面所需的验证脚本。脚本的顺序使我的客户端验证开始触发自定义属性：

(function ($) {
    jQuery.validator.addMethod("requiredif",function (value,element,parameters) {

            var targetId = parameters.otherproperty;
            var targetValue = parameters.otherpropertyvalue;

            var otherpropertyvalue = (targetValue == null || targetValue == undefined ? "" : targetValue).toString();

            var otherpropertyElement = $('#' + targetId);

            if (!value.trim() && otherpropertyElement.val() == otherpropertyvalue) {
                var isValid = $.validator.methods.required.call(this,value,parameters);
                return isValid;
            }

            return true;
        }
    );
})(jQuery);