Programming with DIALOG / DIALOG block structure |
The INPUT sub-dialog implement single record input in fields of the current form.
Each record member variable is bound to the corresponding field of a screen record, in order to manipulate the values that the user enters in the form fields.
The INPUT clause can be used in two forms:
The BY NAME clause implicitly binds the fields to the variables that have the same identifiers as the field names. The variables must be declared with the same names as the fields from which they accept input. The runtime system ignores any record name prefix when making the match. The unqualified names of the variables and of the fields must be unique and unambiguous within their respective domains. If they are not, the runtime system generates an exceptions, and sets the STATUS variable to a negative value.
DEFINE p_cust RECORD cust_num INTEGER, cust_name VARCHAR(50), cust_address VARCHAR(100) END RECORD ... DIALOG INPUT BY NAME p_cust.* BEFORE FIELD cust_name ... END INPUT ... END DIALOG
The FROM clause explicitly binds the fields in the screen record to a list of program variables by position. The number of variables or record members must equal the number of fields listed in the FROM clause. Each variable must be of the same (or a compatible) data types as the corresponding screen field. When the user enters data, the runtime system checks the entered value against the data type of the variable, not the data type of the screen field.
DEFINE c_name VARCHAR(50) c_addr VARCHAR(100) ... DIALOG INPUT c_name, c_addr FROM FORMONLY.field01, FORMONLY.field02 BEFORE FIELD cust_name ... END INPUT ... END DIALOG
The name of an INPUT sub-dialog can be used to qualify sub-dialog actions with a prefix.
In order to identify the INPUT sub-dialog with a specific name, you can use the ATTRIBUTES clause to set the NAME attribute:
INPUT BY NAME p_cust.* ATTRIBUTES (NAME = "cust") ...
Simple record input declared with the INPUT sub-dialog can raise the following triggers:
In the singular INPUT instruction, BEFORE INPUT and AFTER INPUT blocks are typically used as initialization and finalization blocks. In an INPUT sub-dialog of a DIALOG instruction, BEFORE INPUT and AFTER INPUT blocks will be executed each time the focus goes to (BEFORE) or leaves (AFTER) the group of fields defined by this sub-dialog.