Ajout d'un champ ToolValidator

Cet exemple émule la validation de l'outil Ajouter un champ. L'outil Ajouter un champ étant un outil intégré, il ne possède pas de classe ToolValidator. S'il en possédait une, elle aurait l'aspect ci-dessous.

Pour information, voici les paramètres de l'outil Ajouter un champ et leurs types de données :

• 0 – Table en entrée : Type de données composite, inclut toutes les tables
• 1 – Nom du champ : Chaîne
• 2 – Type de champ : Chaîne (LONG, SHORT, DOUBLE, etc.)
• 3 – Précision du champ : Long
• 4 – Echelle de champ : Long
• 5 – Longueur du champ : Long
• 6 – Alias du champ : Chaîne
• 7 – Champ acceptant les valeurs nulles : Booléen
• 8 – Champs requis : Booléen
• 9 – Domaine du champ : Chaîne
• 0 – Table en sortie : sortie dérivée obtenue à partir du paramètre 0

Cet exemple émule la validation de l'outil Ajouter un champ.

class ToolValidator:

    def __init__(self):
        import arcpy 
        self.params = arcpy.GetParameterInfo()

    def initializeParameters(self):
        # The derived output is a clone (copy) of the input
        #
        self.params[10].parameterDependencies = [0]
        self.params[10].schema.clone = True

        # Set up the field type list
        #
        self.params[2].filter.list = ["TEXT", "FLOAT", "DOUBLE",
                                      "SHORT", "LONG", "DATE",
                                      "BLOB", "RASTER"]

        # The default field type is LONG
        #
        self.params[2].value = "LONG"

        # Field scale & Length are disabled for LONG types
        #
        self.params[4].enabled = False
        self.params[5].enabled = False

        # Set the Boolean filters for IsNullable and IsRequired and
        #  their default values
        #
        self.params[7].filter.list = ["NULLABLE", "NON_NULLABLE"]
        self.params[7].value = "NULLABLE"
        
        self.params[8].filter.list = ["REQUIRED", "NON_REQUIRED"]
        self.params[8].value = "NON_REQUIRED"

        return

    def updateParameters(self):
        # Set the default field type value unless the user altered it
        #
        if not self.params[2].altered:
            self.params[2].value = "LONG"

        # Enable/Disable parameters based on field type
        #
        fieldType = self.params[2].value.upper()
        if fieldType in ["TEXT", "BLOB"]:
            self.params[3].enabled = False
            self.params[4].enabled = False
            self.params[5].enabled = True
        elif fieldType in ["FLOAT", "DOUBLE"]:
            self.params[3].enabled = True
            self.params[4].enabled = True
            self.params[5].enabled = False
        elif fieldType in ["SHORT", "LONG"]:
            self.params[3].enabled = True
            self.params[4].enabled = False
            self.params[5].enabled = False
        elif fieldType in ["DATE", "RASTER"]:
            self.params[3].enabled = False
            self.params[4].enabled = False
            self.params[5].enabled = False
        else:
            # Unknown field type.  Internal validation will catch this
            #  and show an error. We might as well return here and let
            #  internal validation do its work.
            #
            return
        
        # Update the output schema with the new field. Don't do anything
        #  unless we have an input value and a field name
        #
        if self.params[0].value and self.params[1].value:
            newField = arcpy.Field()
            newField.name = self.params[1].value
            newField.type = self.params[2].value

            # Set up the field properties based on type of field
            #
            if self.params[3].value and self.params[3].enabled:
                newField.precision = self.params[3].value
            if self.params[4].value and self.params[4].enabled:
                newField.scale = self.params[4].value
            if self.params[5].value and self.params[5].enabled:
                newField.length = self.params[5].value
                
            if self.params[6].value:
                newField.aliasName = self.params[6].value
                
            newField.isNullable = self.params[7].value

            # Note: IsRequired is not a property on a field object -- it's
            #  handled internally by the Add Field system tool.
            # 
            if self.params[9].value:
                newField.domain = self.params[9].value

            # Set the additional field on the output schema
            #
            self.params[10].schema.additionalFields = [newField]

    def updateMessages(self):
        return