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Ocsqlite.h

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/ /

/ / OCSqlite.m

/ / sqlite

/ /

/ / Created by fengsh on 12-12-3.

/ / Copyright (c) 2012 sqlite_Lib. All rights reserved.

/ /

/ *

The main design of the encapsulation of SQLITE is the habit of operation. For lightweight data.

For the amount of data, you need to pay attention to the memory cost.

, /

# import

# import

Enum fieldtype

{

FtInt,ftFloat,ftDouble,ftString,ftBlob,ftBool,ftDate,ftTime,ftDateTime,ftBinary

}

/ *

Field class

Function: mainly used to correspond to the field properties in the database

Field name, field type, field value, field index number

, /

@ interface OCField: NSObject

{

NSString* fieldName

Id fieldValue

Enum fieldtype mtype

Int seq_column

}

-(NSString*) toString

-(NSInteger) toInteger

-(NSDate*) toDate

-(NSString*) toDateString

-(NSString*) toTimeString

-(NSString*) toDateTimeString

-(NSNumber*) toNumber

-(enum fieldtype) getFieldType

@ property (nonatomic) int seq_column

@ end

/ *

Dataset class

Function:

A collection similar to a data source with cursors that can access the data in the data source

, /

@ interface OCDataset: NSObject

{

NSMutableArray* records

NSInteger cursor

}

-(void) clear

-(NSInteger) count

-(BOOL) next

-(BOOL) first

-(BOOL) move: (NSInteger) index

-(OCField*) fieldbyname: (NSString*) fieldname

-(OCField*) indexOffield: (NSInteger) index

@ end

/ *

Simple data definition language operation and encapsulation of database query

Parameter binding is not supported, so you also need extension code on processing blob.

Follow-up improvement

, /

@ interface OCSqlite: NSObject

{

Sqlite3* db

OCDataset* dataset

}

-(id) init

-(BOOL) ConnectToDB: (NSString*) dbfilepath

-(void) DisconnectDB

-(BOOL) startTranslation

-(BOOL) commitTranslation

-(BOOL) rollbackTranslation

-(BOOL) excesql: (NSString*) ddlsql

-(BOOL) query: (NSString*) qysql

@ property (nonatomic,readonly) OCDataset* dataset

@ end

Ocsqlite.m

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/ /

/ / OCSqlite.m

/ / sqlite

/ /

/ / Created by fengsh on 12-12-3.

/ / Copyright (c) 2012 sqlite_Lib. All rights reserved.

/ /

# import "OCSqlite.h"

@ implementation OCField

@ synthesize seq_column

-(id) init

{

Self = [super init]

If (self) {

FieldValue = NULL

Return self

}

Return nil

}

-(void) setfield: (NSString*) name withvalue: (sqlite3_value*) value withtype: (NSString*) tp

{

FieldName = name

NSString* result = @ ""

If ([tp isEqualToString:@ "integer"] | | [tp isEqualToString:@ "smallint"])

{

Mtype = ftInt

FieldValue = (id) sqlite3_value_int (value)

Return

}

Else if ([tp isEqualToString:@ "boolean"])

{

Mtype = ftBool

}

Else if ([tp isEqualToString:@ "float"])

{

Mtype = ftFloat

}

Else if ([tp isEqualToString:@ "double"] | | [tp isEqualToString:@ "real"])

{

Mtype = ftDouble

}

Else if ([tp isEqualToString:@ "text"] | | [tp isEqualToString:@ "varchar"])

{

Mtype = ftString

}

Else if ([tp isEqualToString:@ "blob"])

{

Mtype = ftBlob

Return

}

Else if ([tp isEqualToString:@ "date"])

{

Mtype = ftDate

}

Else if ([tp isEqualToString:@ "time"])

{

Mtype = ftTime

}

Else if ([tp isEqualToString:@ "timestamp"])

{

Mtype = ftDateTime

}

Else if ([tp isEqualToString:@ "binary"])

{

Mtype = ftBinary

Return

}

Char* floatstr = (char*) sqlite3_value_text (value)

If (floatstr) {

Result = [NSString stringWithCString:floatstr encoding:NSUTF8StringEncoding]

}

FieldValue = result

}

-(NSString*) toString

{

Return (NSString*) fieldValue

}

-(NSInteger) toInteger

{

Return (int) fieldValue

}

-(NSNumber*) toNumber

{

Switch (mtype) {

Case ftFloat:

Return [NSNumber numberWithFloat: [(NSString*) fieldValue floatValue]]

Break

Case ftDouble:

Return [NSNumber numberWithDouble: [(NSString*) fieldValue doubleValue]]

Break

Case ftBool:

Return [NSNumber numberWithBool: [(NSString*) fieldValue boolValue]]

Break

Default:

Return [NSNumber numberWithInt: [(NSString*) fieldValue intValue]]

Break

}

}

-(NSString*) toDateString

{

NSDateFormatter* fmt = [NSDateFormatter alloc] init] autorelease]

[fmt setDateFormat:@ "yyyy-mm-dd"]

NSDate* date = [fmt dateFromString:fieldValue]

NSString* datestr = [fmt stringFromDate:date]

Return (datestr==nil)? @ "": datestr

}

-(NSString*) toTimeString

{

NSDateFormatter* fmt = [NSDateFormatter alloc] init] autorelease]

[fmt setDateFormat:@ "HH:mm:ss"]; / / H is 0 murine 23 h is 1-12

NSDate* time = [fmt dateFromString:fieldValue]

NSString* timestr = [fmt stringFromDate:time]

Return (timestr==nil)? @ "": timestr

}

-(NSString*) toDateTimeString

{

NSDateFormatter* fmt = [NSDateFormatter alloc] init] autorelease]

[fmt setDateFormat:@ "yyyy-MM-dd HH:mm:ss"]; / / H is 0 murine 23 h is 1-12

NSDate* datetime = [fmt dateFromString:fieldValue]

NSString* dtimestr = [fmt stringFromDate:datetime]

Return (dtimestr==nil)? @ "": dtimestr

}

-(NSDate*) toDate

{

NSDateFormatter* fmt = [[NSDateFormatter alloc] init]

[fmt setDateFormat:@ "yyyy-MM-dd HH:mm:ss"]

NSDate* date = [fmt dateFromString:fieldValue]

Return date

}

-(enum fieldtype) getFieldType

{

Return mtype

}

@ end

@ implementation OCDataset

-(id) init

{

Self = [super init]

If (self) {

Cursor =-1

Records = [[NSMutableArray alloc] init]

Return self

}

Return nil

}

-(void) dealloc

{

[records release]

[super dealloc]

}

-(void) reset

{

Cursor = 0

}

-(void) fillData: (sqlite3_stmt*) cmd

{

NSInteger colcount = sqlite3_column_count (cmd)

NSMutableDictionary* fields = [NSMutableDictionary alloc] init] autorelease]

For (NSInteger I = 0; I < colcount; iTunes +) {

Char* fieldname = (char*) sqlite3_column_name (cmd, I)

NSString* strfieldname = [NSString stringWithCString:fieldname encoding:NSUTF8StringEncoding]

Sqlite3_value* mvalue = sqlite3_column_value (cmd, I)

Char* ity = (char*) sqlite3_column_decltype (cmd, I)

NSString* stype = [NSString stringWithCString:ity encoding:NSUTF8StringEncoding]

/ / int type = sqlite3_column_type (cmd, I)

OCField* field = [[OCField alloc] init]

[field setfield:strfieldname withvalue:mvalue withtype:stype]

Field.seq_column = I

[fields setObject:field forKey:strfieldname]

}

[records addObject:fields]

}

-(void) clear

{

[records removeAllObjects]

Cursor =-1

}

-(NSInteger) count

{

Return [records count]

}

-(OCField*) fieldbyname: (NSString*) fieldname

{

NSMutableDictionary* dic = [records objectAtIndex:cursor]

Return (OCField*) [dic objectForKey:fieldname]

}

-(BOOL) next

{

+ + cursor

Int rcount = [records count]

If (cursor 0) {

Cursor = 0

Return YES

}

Else

{

Cursor =-1

Return NO

}

}

-(BOOL) move: (NSInteger) index

{

Int idx = index-1

If (- 1 < idx < [records count]) {

Cursor = idx

Return YES

}

Return NO

}

-(OCField*) indexOffield: (NSInteger) index

{

OCField* ret = nil

Int ct = 0

NSMutableDictionary* dic = [records objectAtIndex:cursor]

For (NSString* key in dic)

{

Ret = [dic objectForKey:key]

If (index = = ct)

Break

Else

Ct++

}

Return ret

}

@ end

@ implementation OCSqlite

@ synthesize dataset

-(id) init

{

Self = [super init]

If (self) {

Dataset = [[OCDataset alloc] init]

Return self

}

Return nil

}

-(void) dealloc

{

[dataset release]

Sqlite3_close (db)

[super dealloc]

}

-(BOOL) ConnectToDB: (NSString*) dbfilepath

{

BOOL successful

Successful = sqlite3_open ([dbfilepath UTF8String], & db) = = SQLITE_OK

If (! successful) {

Sqlite3_close (db)

Return NO

}

Return YES

}

-(void) DisconnectDB

{

Sqlite3_close (db)

}

-(BOOL) excesql: (NSString*) ddlsql

{

Char* err

If (sqlite3_exec (db, [ddlsql UTF8String], NULL, NULL, & err)! = SQLITE_OK)

{

Return NO

}

Return YES

}

-(BOOL) query: (NSString*) qysql

{

Sqlite3_stmt* cmd

If (sqlite3_prepare_v2 (db, [qysql UTF8String],-1, & cmd, nil)! = SQLITE_OK)

{

Return NO

}

[dataset clear]

While (sqlite3_step (cmd) = = SQLITE_ROW)

{

[dataset fillData:cmd]

}

[dataset reset]

Sqlite3_finalize (cmd)

Return YES

}

-(BOOL) startTranslation

{

Char* err

If (sqlite3_exec (db, "begin transaction", NULL, NULL, & err)! = SQLITE_OK)

{

Return NO

}

Return YES

}

-(BOOL) commitTranslation

{

Char* err

If (sqlite3_exec (db, "commit transaction", NULL, NULL, & err)! = SQLITE_OK)

{

Return NO

}

Return YES

}

-(BOOL) rollbackTranslation

{

Char* err

If (sqlite3_exec (db, "rollback transaction", NULL, NULL, & err)! = SQLITE_OK)

{

Return NO

}

Return YES

}

@ end

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