RAD Studio VCL Reference
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Represents the field's value as a 32-bit integer.
property AsInteger: Longint;
__property Longint AsInteger;
Use AsInteger to read the value of the field's data into an integer, or to assign an integer value to the contents of the field. TField does not support integer values, and raises an exception when an attempt is made to get or set the AsInteger property.
Descendants of TField that represent integer fields or that support conversions between the field's Value property and an integer value, override AsInteger to read and write the value of the field as an integer value.
Delphi Examples:
{ This example uses the BeforeInsert event to do data validation. If the StrToInt function raises an exception, the edit control’s contents are set to a valid value so that the assignment to the INTEGER field in the dataset will succeed. Continuing after the exception causes a '0' to be placed in the PORTA field. DataSet design: This example requires a ClientDataSet, a DBGrid, a DataSource and a DBNavigator. Name the ClientDataSet CDS. Set the DataSet property in the DataSource to CDS and name that DataSource DS. Set the DataSource in the DBNavigator to DS the DataSource in the DBGrid to DS. Right click on CDS and select the Fields Editor, then right click on the Field Editor form and create two fields by selecting "new field". In the field configuration window, set the name to HOST, the Component value will automatically be set to CDSHOST. Set the filed type to String. In the field configuration window for the second field, set the name to PORTA, the Component value will automatically be set to CDSPORTA. Set the field type to Integer. The file used to load CDS must have an attribute name of HOST with an attribute type of string and an attribute name of PORTA with an attribute type of integer. Add DB, DBCtrls, Grids, DBGrids and DBClient to the uses clause. } {$IFNDEF UNICODE} uses SwSystem; {$ENDIF} procedure TForm1.Button3Click(Sender: TObject); begin CDS.Insert; CDS.FieldByName('PORTA').AsInteger := StrToInt(Edit1.Text); CDS.Post; end; procedure TForm1.CDSBeforeInsert(DataSet: TDataSet); begin try { Make sure edit field can be converted to integer -- this will raise an exception if it can’t } StrToInt(Edit1.Text); except Edit1.Text := '0'; end; end; procedure TForm1.FormCreate(Sender: TObject); begin {$IFDEF UNICODE} CDS.LoadFromFile(GetCurrentDir + '\CDS.XML'); {$ELSE} CDS.LoadFromFile(gsAppPath + 'CDS.XML'); {$ENDIF} end;
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