This document contains code from the datalib.ring library that defines classes for database connectivity and model-view-controller implementation in Ring.
The Database class handles database connections and queries. The ModelBase class extends Database and adds methods for CRUD operations on a model object. It determines the table name from the class name.
The ControllerBase class is the base class for controllers. It dynamically creates the view and model objects based on the controller class name. It also contains routing logic and pagination methods. These classes provide a framework for building MVC applications with Ring and connecting to a database.
6. Ring Documentation, Release 1.3
oUser = new UsersModel
oUser.Connect()
lResult = oUser.FindWith("username",aPageVars["username"])
new page {
if lResult
if sha256(aPagevars["password"]+oUser.Salt) = oUser.pwhash
text ("Correct Password!")
aPageVars["sessionid"] = str2hex(randbytes(32))
oUser.UpdateColumn("sessionid",aPageVars["sessionid"])
cookie("sessionid",aPageVars["sessionid"])
else
text ("Bad password!")
ok
else
text("Bad User Name!")
ok
}
oUser.Disconnect()
The next code for checking if the user needs to login or not
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Load "ex25_users.ring"
Import System.Web
oUser = new UsersModel
oUser.Connect()
lResult = oUser.FindWith("sessionid",aPageVars["sessionid"])
new page {
if lResult
text("User Name : " + oUser.username )
else
text("Please Login First!")
ok
}
oUser.Disconnect()
42.22 Database, ModelBase & ControllerBase classes
In this section we will see some code from datalib.ring
The next code presents the Database, ModelBase & ControllerBase classes
Import System.Web
Class Database
cServer = "localhost"
cUserName = "root"
cPassword = "root"
cDatabase = "mahdb"
Func Connect
42.22. Database, ModelBase & ControllerBase classes 313
7. Ring Documentation, Release 1.3
con = mysql_init()
mysql_connect(con, cServer, cUserName, cPassWord,cDatabase)
Func Disconnect
mysql_close(con)
Func Query cQuery
mysql_query(con,cQuery)
Func QueryResult
return mysql_result(con)
Func QueryResultWithColumns
# return columns names + query result
return mysql_result2(con)
Func QueryValue
aResult = mysql_result(con)
if islist(aResult) and len(aResult) >= 1
aResult = aResult[1]
if len(aResult) >= 1
return aResult[1]
ok
ok
return 0
Func EscapeString x
if isstring(x)
return MySQL_Escape_String(con,x)
else
return MySQL_Escape_String(con,string(x))
ok
Private
con = NULL
Class ModelBase from Database
cTableName = ""
cSearchColumn = "name"
aColumns = []
aQueryResult = []
ID = 0
# set table name from class name
classname = lower(classname(self))
if right(classname,5) = :model
cTablename = left(classname,len(classname)-5)
ok
Func Insert
cValues = ""
for x in aColumns
cValues += "'" + EscapeString(aPageVars[x]) + "',"
42.22. Database, ModelBase & ControllerBase classes 314
8. Ring Documentation, Release 1.3
Next
cValues = left(cValues,len(cValues)-1) # remove last comma
cColumns = ""
for x in aColumns
cColumns += x + ","
next
cColumns = left(cColumns,len(cColumns)-1)
query("insert into " + cTableName + "("+cColumns+") values (" +
cValues + ")" )
Func Update nID
cStr = ""
for x in aColumns
cStr += x + " = '" + EscapeString(aPageVars[x]) + "' , "
# the space after comma is necessary
Next
cStr = left(cStr,len(cStr)-2)
query("update " + cTableName + " set " + cStr + " where id = " + nID )
Func UpdateColumn cColumn,cValue
query("update " + cTableName + " set " + cColumn + " = '" +
EscapeString(cValue) + "' where id = " + self.ID )
Func Count cValue
query("SELECT count(*) FROM " + cTableName +
" where "+cSearchColumn+" like '" + EscapeString(cValue) + "%'")
return queryValue()
Func Read nStart,nRecordsPerPage
query("SELECT * FROM "+ cTableName+" limit " + EscapeString(nStart) + "," +
EscapeString(nRecordsPerPage) )
aQueryResult = queryResult()
Func Search cValue,nStart,nRecordsPerPage
query("SELECT * FROM "+ cTableName+" where "+cSearchColumn+" like '" +
EscapeString(cValue) + "%'" +
" limit " + EscapeString(nStart) + "," + EscapeString(nRecordsPerPage) )
aQueryResult = queryResult()
Func Find nID
query("select * from " + cTableName + " where id = " + EscapeString(nID) )
aResult = queryResult()[1]
# move the result from the array to the object attributes
ID = nID
cCode = ""
for x = 2 to len(aResult)
cCode += aColumns[x-1] + " = hex2str('" + str2hex(aResult[x]) + "')" + nl
next
eval(cCode)
Func FindWith cColumn,cValue
42.22. Database, ModelBase & ControllerBase classes 315
9. Ring Documentation, Release 1.3
query("select * from " + cTableName + " where "+cColumn+" = '" +
EscapeString(cValue) + "'" )
aResult = queryResult()
if len(aResult) > 0
aResult = aResult[1]
else
return 0
ok
# move the result from the array to the object attributes
ID = aResult[1]
cCode = ""
for x = 2 to len(aResult)
cCode += aColumns[x-1] + " = hex2str('" + str2hex(aResult[x]) + "')" + nl
next
eval(cCode)
return 1
Func Delete ID
query("delete from " + cTableName + " where id = " + EscapeString(ID) )
Func Clear
cCode = ""
for x in aColumns
cCode += x + ' = ""' + nl
next
eval(cCode)
Func LoadModel
# create the columns array
query("SELECT * FROM "+ cTableName + " limit 0,1")
aQueryResult = QueryResultWithColumns()[1]
for x = 2 to len(aQueryResult)
aColumns + lower(trim(aQueryResult[x]))
next
# create attribute for each column
for x in aColumns
addattribute(self,x)
next
Func Connect
Super.Connect()
if nLoadModel = 0
nLoadModel = 1
LoadModel()
ok
private
nLoadModel = 0
Class ControllerBase
42.22. Database, ModelBase & ControllerBase classes 316
10. Ring Documentation, Release 1.3
nRecordsPerPage = 5
nRecordsCount = 0
nPagesCount = 0
nActivePage = 0
# Dynamic creation of oView = new tablenameView and oModel = new tablename.Model
classname = lower(classname(self))
if right(classname,10) = :controller
tablename = left(classname,len(classname)-10)
cCode = "oView = new " + tablename+"View" + nl
cCode += "oModel = new " + tablename+"Model" + nl
eval(cCode)
oModel.connect()
ok
cSearchName = "searchname"
cPart = "part"
cPageError = "The page number is not correct"
cLast = "last"
cOperation = "operation"
cRecID = "recid"
aColumnsNames = ["id"]
for t in oModel.aColumns
aColumnsNames + t
next
cMainURL = website + "?"
func Routing
switch aPageVars[cOperation]
on NULL showtable()
on :add addrecord()
on :save saverecord()
on :delete deleterecord()
on :edit editrecord()
on :update updaterecord()
off
func ShowTable
nRecordsCount = oModel.Count( aPageVars[cSearchName] )
nPagesCount = ceil(nRecordsCount / nRecordsPerPage)
if aPageVars[cPart] = cLast
aPageVars[cPart] = string(nPagesCount)
ok
nActivePage = number(aPageVars[cPart])
if nActivePage = 0 nActivePage = 1 ok
if ( nActivePage > nPagesCount ) and nRecordsCount > 0
ErrorMsg(cPageError)
return
ok
42.22. Database, ModelBase & ControllerBase classes 317