跨不同ValidationAttribute的C＃共享ValidationContext失败

问题描述

要使用一系列自定义验证属性（如下所述）对输入模型进行验证。

如果第一个验证属性（即“ ValidatorAttributeOne”）的验证结果为true，则无需处理“ ValidatorAttributeTwo”验证逻辑。

要获得分配给“ validationContext.Items”字典的“ ValidationAttributeOne”的有效结果，则认为“ validationContext”将在同一http请求中的不同“ ValidationAttributes”之间共享，但下面的行始终抛出异常

var isDependedFilterValidated = (bool?)validationContext.Items[dependedFilter]

“ message”：“字典中不存在给定键'ValidationAttributeOne'。”，

public class ValidatorAttributeOne : ValidationAttribute
{
    protected override ValidationResult IsValid(object value,ValidationContext validationContext)
    {
       //custom validation

        validationContext.Items["ValidatorAttributeOne"] = true;
        return ValidationResult.Success;
    }
}


public class ValidatorAttributeTwo : ValidationAttribute
{
    private readonly string dependedFilter = default(string);

    public UsernamesEmailValidatorAttribute()
    {           
    }

    public UsernamesEmailValidatorAttribute(string filter)
    {
        dependedFilter = filter;
    }

    protected override ValidationResult IsValid(object value,ValidationContext validationContext)
    {
        var isDependedFilterValidated = (bool?)validationContext.Items[dependedFilter];

        if (isDependedFilterValidated == false)
        {
            //custom validation logic                
        }

        return ValidationResult.Success;
    }
}

public class CustomeModel
{ 
    [ValidatorAttributeOne ]
    [ValidatorAttributeTwo("ValidatorAttributeOne")] 
    public string usernames { get; set; }      
}  

解决方法

首先，如果您不想在第一个为true时执行validationContext，则两个自定义验证属性不能共享validateContext。您可以将两个validateAttributes的IsValid方法的内容设置在一起。

例如：

public class ValidationAttributeThree : ValidationAttribute
    {
        protected override ValidationResult IsValid(object value,ValidationContext validationContext)
        {
            
            if (ValidationAttributeOne IsValid method Content is true) {
                return ValidationResult.Success;
             }
            else if(ValidationAttributeTwo IsValid method Content is true){
               return new ValidationResult("ValidationAttributeOne error message");
            }else{
                return new ValidationResult("ValidationAttributeOne error message"+"ValidationAttributeTwo error message");
            }
                
        }
    }