TDataSet
Razred TDataSet vsebuje informacije o nizih podatkov v podatkovni plasti.
Vsebina
Lastnosti niza podatkov
Dim L as TLayer, D As TDataSet, I As Long
L = [Neka plast]
For I = 0 To L.DataSetCount - 1
D = L.DataSets (I)
Message ("Lastnosti niza podatkov",
"Ime: " + D.Name + Line +
"Dodatno ime: " + D.Alias + Line +
"Komentar: " + D.Comment + Line +
"ID: $" + IntToHex (D.ID)
"Podatkovna plast: " + D.Parent.Name
)
NextName
Lastnost Name določa ime niza podatkov.
| Property TDataSet.Name As String | ||
| Result | String | . |
Alias
Lastnost Alias določa drugo ime niza podatkov v podatkovni plasti.
| Property TDataSet.Alias As String | ||
| Result | String | . |
Comment
Lastnost Comment določa komentar niza podatkov.
| Property TDataSet.Comment As String | ||
| Result | String | . |
ID
Lastnost ID vrne unikatno identifikacijsko kodo, ki se samodejno kreira pri kreiranju dataseta in se nikdar ne spremeni.
| RO Property TDataSet.ID As Long | ||
| Result | Long | . |
Parent
Lastnost Parent določa kateri podatkovni plasti imenovan niz podatkov pripada.
| Property TDataSet.Parent As TLayer | ||
| Result | TLayer | . |
DatasetType
Lastnost DatasetType .
| Property TDataSet.DatasetType As Long | ||
| Result | Long | . |
Lookup
Lastnost Lookup .
| Property TDataSet.Lookup As String | ||
| Result | String | . |
Polja
FieldAdd
Lastnost FieldAdd doda nov objekt tipa TField (polje) v nizu podatkov, ter kot rezultat vrne novo kreiran objekt.
| RO Property TDataSet.FieldAdd As TField | ||
| Result | TField | . |
Dim NewField As TField, D As TDataSet
Dim L as TLayer
L = [Neka plast]
If Assigned (L) Then
D = L.Datasets (0)
NewField = D.FieldAdd
NewField.Name = 'Ime novega polja'
NewField.Alias = 'INP'
NewField.Name = 'To je novo polje'
L.Store
EndIFFieldCount
Lastnost FieldCount vrne število polj v nizu podatkov..
| RO Property TDataSet.FieldCount As Long | ||
| Result | Long | . |
FieldInsert
Lastnost FieldInsert vrine novo polje v obstoječi niz podatkov.
| RO Property TDataSet.FieldInsert (Index As Long) As TField | ||
| Index | Long | Mesto novega polja. |
| Result | TField | Referenca na novo polje tipa TField. |
Dim NewField As TField, D As TDataSet
D = [SomeLayer].Datasets (0)
NewField = D.FieldInsert (1)
NewField.Name = 'ImeNovegaPolja'
[SomeLayer].StoreFields
Lastnost Fields vrne index-ti Tfield objekt v nizu podatkov.
| RO Property TDataSet.Fields (Index As Long) As TField | ||
| Index | Long | Index polja. Prvi ima index 0. |
| Result | TField | TField objekt. |
Razno
CurrentRecord
Lastnost CurrentRecord Lastnost vsebuje kazalec na tekoči zapis, in je enaka za TLayer.CurrentRecord lastnosti in TField.CurrentRecord lastnosti. Če jo spremenite, se spremeni tudi v obeh naštetih objektih. Uporabna je npr v TField.AsString lastnosti in v nekaterih drugih za ta razred.
| Property TDataSet.CurrentRecord As TRecord | ||
| Result | TRecord | . |
Dim L as TLayer
L = [Neka plast]
L.Datasets (0).CurrentRecord = L.AllRecords.Items (0)AddFieldsFromFile
Metoda AddFieldsFromFile .
| Method TDataSet.AddFieldsFromFile (FileName As String) | ||
| FileName | String | . |