PB programming popular start
Zhang Jinzhu
The first chapter is generally used
1. The start of the program, the OPEN event of Application.
Exit program routine: HALT is exit function
Int Surequit
Surequit = 2
Surequit = MessageBox ("Exit System", "Please confirm the saved data before exiting", Question!, Okcancel !, 2)
If Surequit = 1 Then Halt
2, variable definition valid range:
◎ Declare-Globe global variable, all procedures are effective
◎ Declare-instance local variable can be valid in an object (eg, a form, app, etc.)
◎ Variables defined in the module can be valid in the current module
Definition: (Incounting case in PB is not sensitive)
Constant string ls_homecity = "boston" constant
INT A integer
CHAR C character
Boolean B Boolean
String a string type
Arch of String a [1000] 1000, 0 ~ 1000
String a [3 to 30] array element is 3 to 30, the initial one is a [3], the last one is a [30]
String a [100, 3TO 30] two-dimensional array, one dimension is 0 ~ 100, 2D 3 to 30
String a [] becomes the array, assigns the value (such as A [30] = 333) automatically assigns memory.
Get up UPPERBOUND, the lower bound LowerBound.
operating:
A = "AAAA" "VVVBB" B C
String (b) Convert B into a string type
Integer ("333333333333") will be converted to "333333333333" string 3333333333333
A = A B * C ^ D / E / F% G
◎ Note: The space is subject to a space before the reduction is used to avoid the BUG of PB7.0.
3, function definition:
The first line is the return type and function name, the second line is the variable type and variable name, Tab key plus.
Return is the return of the function, as if the C language is the same, the RETURN function ends
4, open the window
Open (window name)
OpenWithParm (window name, parameter, parent window 5, open sub-forms in the MDI form Stamped pattern Open OpenSheet (Subform, Parent Windhead Name, 1, Layered!) Tile style Open OpenSheet (Subform, Parent Windhead Name, 1, Original!) If you are written under the form of the parent form, you can use opensheet (child form, this, 1, original!) The third parameter represents the location of the new form in the parent form menu. 6, the basic properties of the control Control name. X X coordinate Control name. Y Y coordinate Control name. Width wide Control name. Height High ... (Others can see the properties window in the editor) 7, adjust the form mode this.windowState = maximized! Form .WindowState = maximized! Form Maximization (other properties window in the editor) 8, INI file read and write Examples There is an INI file called "mnr.ini", (path in the program where the program is located) is as follows: [An action] Preload = YES You can read it as follows: A = ProfileString ("Mnr.ini", "Action", "preload", "aaa") A is a variable, "AAA" is the default data when the data item is in the data item. You can write it with the following statement (write value yes): SetProfileString ("Mnr.ini", "Action", "preload", "yes") 9. Variables to be used throughout the program You can define a structure first, and then define the structure type variable in Globe Declare, manage it. 10, main grammar unit Condition judgment How how IF I how to do How to il IF how to do END IF Choose Case variable Case IS <3 ... Case 4 to 7 ... Case Else ... End chaoose Circulation to a greater than 5 DO A = a 1 LOOP Until A> 5 do while a <= 5 A = a 1 Loop DO A = a 1 LOOP Until A> 5 DO Until A> 5 A = a 1 Loop Jump out of the cycle exit, continue the next round of cycling Continue 11, message box Messagebox (title, information) Other help, check the index MessageBox 12, get the current time now () SLE_BEGINTIME.TEXT = String (now (), "YYYY-MM-DD 10:00:00") If it is 2002-7-14 17:22:21 seconds, the output is 2002-7-14 10:00:00 13, list box application DDLB_BSC.RESET () Clear List Box I = 1 Do While i <= UpperBound (WINBSC) IF WINBSC [I] = "". DDLB_BSC.ADDITEM (WINBSC [i]) adds content items to list boxes I = i 1 Loop Chapter II Application Database 1, the use of the DataWindow control Create a DataWTwOw object DW_HWTJ first, add a DataWindow control DW_REP in the form, and finally set the DataWindow's DataObject property to dw_hwtj. a) I write the selected line function, using the DataWindow control Click event if row = 0 Then Return If Nowrow <> row and norow> = 0 THEN This.SelectRow (nowrow, false) END IF This.selectrow (Row, True) Nowrow = row b) I write the sort function, using the Double-click event for the DataWindow control IF dwo.type = "column" then LS_COLUMNNAME = dwo.name END IF if Nowstate = 'a' TENTHIS.SETSORT (LS_COLUMNNAME "D") NowState = 'd' Else This.setsort (Ls_ColumnName "A") NowState = 'a' END IF This.sort () (Effect, double-click once on a list, sort forward, once again, reverse sorting) c) Sorting DW_REP.SETSORT ("BSCMC A, XQH A, XQMC A") DW_REP.SORT () (Press BSCMC first, press XQH, press the XQMC to be sorted forward) d) Save to XLS files DW_REP.SAVEAS ('', Excel5!, true) e) read and write: Write w_netrep_cell.dw_rep.Object.tchpzzs [i] = a Read a = w_netrep_cell.dw_rep.object.tchpzzs [i] 2, establish a connection to the database 1) Definition Transaction Localdb 2) Set MyTrans.dbms = "as" MyTrans.Database = "SDA" MyTrans.logpass = "DEF" MyTrans.ServerName = "dbo" MyTrans.logid = "ABC" MyTrans.dbparm = "" " MyTrans.lock = "" MyTrans.Userid = "ABC" MyTrans.autocommit = true 3) connection Connect connect use localdb; Disconnect Using Localdb on DISCONNECT; 4) Query multi-line data from the library: (query statement is cured) Connect use localdb; // connection if Localdb.sqlcode <0 THEN MessageBox ("Connect Local Database Failed ...", Localdb.sqlerrtext) Return 1 END IF Declare my_cursor cursor for // Defining a cursor SELECT BSC from BSC ORDER BY BSC Using Localdb; // Execute Query I = 1; Open my_cursor; // Open the cursor Do while not localdb.sqlcode = 100 // until the end IF i> Upperbound (WINBSC) THEN EXIT FETCH MY_CURSOR INTO: WINBSC [i]; // Extract data items I = i 1 Loop Close my_cursor; // Close the cursor Disconnect using localdb; // disconnected 5) Query a row of data from the library: (Query statement is cured) Help In the routine, ":" After adding a string refers to the variable of the string Select Employee.emp_lname, Employee.emp_fname INTO: EMP_LNAME,: EMP_FNAME From Employee WHERE EMPLOYE.EMP_NBR =: EMP_NUM USING EMP_TRAN; 6) Use in data update, deletion, increase, build table, etc.: Note: Dynamic SQL Format 1 Statement ... Dynamic SQL Format 4 Statement, which is very clear (see Sample) Perform a statement directly: Execute Immediate SqlStatement {Using TransactionObject}; Help is very clear, there are not many talks here. 7) Non-cured query statement: This is very important for improving software flexibility, but it is very simple, only on Help is: Declare my_cursor Dynamic Cursor for SQLSA String SQL1, SQL2 SQL1 = "SELECT EMP_ID from Department Where Salary> 90000" SQL2 = "SELECT EMP_ID From Department & <- this is a branch connection symbol, a space behind a space? WHERE SALY> 20000 " IF deptid = 200 THEN Prepare Sqlsa from: SQL1 Using SQLCA; Else Prepare SQLSA from: SQL2 Using SQLCA; END IF Open dynamic my_cursor; summary: There are not many content, but the main things are here, others should understand in practice, these knowledge is developed, the knowledge and depth are enough to start and standard MIS systems. The SQL statement helps have been sufficient, more talks in detail, will not be described. 2002-7-14
