Class DatabasePropertyValidationAttribute

Allows you to write a formula against properties that are automatically evaluated to validate changes

Inheritance
object
Attribute
ValidationAttribute
DatabaseValidationAttribute
DatabasePropertyValidationAttribute
Inherited Members
Namespace: LemonEdge.API.Attributes.Validation
Assembly: LemonEdge.API.dll
Syntax
[AttributeUsage(AttributeTargets.Property, AllowMultiple = true)]
public class DatabasePropertyValidationAttribute : DatabaseValidationAttribute
Remarks

For instance you can validate properties using custom scripts like so:

public interface MyItem
{
    bool ValidateX { get; set; }

    [DatabasePropertyValidation(
        //checkOnLamda. Only validate this property if this returns true 
        "MyItem." + nameof(ValidateX),
        //validOnLamda. If returns false then the validation fails and the following message returns why
        //This script uses LemonEdge.Core.FormulaFunctionsWithContext. So you can access the Cache, User, and Updater. 
        //You can also write any c# script, not just a single line formula
        "var itemVaue = MyItem.AmountX; return itemValue > 100;",
        //message. Reason for validation failure
        "AmountX must be greater than 100 if ValidateX is true.")]
    Int16 AmountX { get; set; }
}

Constructors

DatabasePropertyValidationAttribute(string, string, string)

Validates this property whenever the item is changed

Declaration
public DatabasePropertyValidationAttribute(string checkOnLamda, string validOnLamda, string message)
Parameters
Type Name Description
string checkOnLamda

Only runs the calidOnLamda check if this statement is true, otherwise it returns valid
string validOnLamda

valid if this check is true, false otherwise and returns message
string message

Returns message if validOnLamda is false

Properties

TypeId

Have to override this if AllowMultiple is true

Declaration
public override object TypeId { get; }
Property Value
Type Description
object
Overrides

Methods

IsValid(object, IEntityUpdater, IReadOnlyCache, UserInfo, ValidationContext)

The validation method to return if the item, and changes, are valid or not

Declaration
protected override Task<ValidationResult> IsValid(object value, IEntityUpdater dbCon, IReadOnlyCache cache, UserInfo user, ValidationContext validationContext)
Parameters
Type Name Description
object value

The item to be validated
IEntityUpdater dbCon

A connection to the database to use for validation
IReadOnlyCache cache

A local cache of current items to speed validation
UserInfo user

The current logged in user who made the changes
ValidationContext validationContext

The validation context across all changes
Returns
Type Description
Task<ValidationResult>

A task holding the validation result
Overrides

Extension Methods

See Also