MySQL数据库操作类(转)
//
//在长时间的开发工作中,慢慢做了一些类库,下面这个是一个数据库操作类,欢迎大家交流
//联系方式 QQ:413133880 Email: QQ413133880@gmail.com
unit MySQLData;
interface
uses
SysUtils, Classes,DB,Variants,StdCtrls,Dialogs,myaccess;
type
TMySQL = class(TComponent)
private
Connection: TMyConnection;
Query: TMyQuery;
Table: TMyTable;
FConnectionString:string;
procedure InitQuery(InputQuery: TMyQuery; QueryString: String);
function CheckParaEqual(QueryString: String; ParameterList: TStringList):Boolean;
procedure InitParameter(InputQuery:TMyQuery;QueryString:string;ParameterList:TStringList);
public
constructor Create(ConnectionString: String);overload;
constructor Create(Server:string='localhost';Port:Integer=3306;LoginName:string='root';Password:string='';Database:string='';CharSet:string='latin1');overload;
destructor Destory;virtual;
procedure SetConnectionString(ConnectionString: string);
function GetConnection():TMyConnection;overload;virtual;
function GetConnection(ConnectionString: String): TMyConnection;overload;virtual;
function GetQuery: TMyQuery;overload;virtual;
procedure GetQuery(InputQuery: TMyQuery; QueryString: String);overload;virtual;
procedure GetQuery(InputQuery:TMyQuery; QueryString: String; ParameterList: TStringList);overload;virtual;
function GetTable: TMyTable;overload;virtual;
function GetTable(TableName: String): TMyTable;overload;virtual;
function GetTable(TableName: String; Connection: TMyConnection):TMyTable;overload;virtual;
function GetExecuteScalar(QueryString: String): Variant;overload;virtual;
function GetExecuteScalar(QueryString: String; ParameterList: TStringList): Variant;overload;virtual;
function GetExecuteNoQuery(ExecuteSQL:String):Boolean;overload;virtual;
function GetExecuteNoQuery(ExecuteSQL: String; ParameteList: TStringList):Boolean;overload;virtual;
function GetParameteList: TStringList;overload;virtual;
function GetParameteList(ParameterString:string;SplitString: String=';'):TStringList;overload;virtual;
function BindList(QueryString: String;List:TStringList):TStringList;overload;virtual;
procedure BindComboBox(InputComboBox: TComboBox; QueryString: String);virtual;
procedure GetTableNames(Connection: TMyConnection; List: TStringList);overload;virtual;
procedure GetTableNames(List: TStringList);overload;virtual;
procedure GetFieldNames(TableName:string;List: TStringList);overload;virtual;
procedure GetFieldNames(Connection: TMyConnection;TableName:string; List: TStringList);overload;virtual;
function GetStringList: TStringList;virtual;
procedure AddToComboboxItem(InputComboBox:TComboBox;List:TStringList);virtual;
function getBackupInSertSQL(Connection: TMyConnection;TableName: string;
InsertEachTime:Integer=1):TStringList;overload;virtual;
function getBackupInSertSQL(QueryString: string;
InsertEachTime:Integer=1):TStringList;overload;virtual;
function StrNum(ShortStr, LongString: string): Integer;virtual;
function StrSub(psInput: String; BeginPlace, CutLeng: Integer): String;virtual;
function StrFind(ShortStr, LongStrIng: String): Integer;virtual;
function replace(Source, Old, New: STRING): string;virtual;
function StrCut(SourceString:WideString;BeginString:WideString;EndString:WideString):WideString ;virtual;
published
property ConnectionString:string write setConnectionString;
end;
procedure Register;
implementation
procedure Register;
begin
RegisterComponents('ADO', [TMySQL]);
end;
constructor TMySQL.Create(ConnectionString:String);
begin
try
except
ShowMessage('创建ADO对象失败');
Exit;
end;
end;
destructor TMySQL.Destory;
var i:Integer;
begin
try
Self.Connection.Close;
Self.Query.Close;
Self.Table.Close;
Self.Query.Free;
Self.Table.Free;
Self.Connection.Free;
except
for i:=0 to Self.ComponentCount-1 do
if Self.Components[i]<>nil then
Self.Components[i].Free;
ShowMessage('内存可能溢出');
end;
end;
procedure TMySQL.SetConnectionString(ConnectionString: string);
begin
if Self.Connection.Connected then
end;
function TMySQL.GetConnection():TMyConnection;
begin
Result:=Self.Connection;
end;
function TMySQL.GetConnection(ConnectionString: String): TMyConnection;
var temp:TMyConnection;
begin
end;
function TMySQL.GetQuery: TMyQuery;
var TempQuery:TMyQuery;
begin
TempQuery:=TMyQuery.Create(nil);
TempQuery.Connection:=Self.Connection;
Result:=TempQuery;
end;
procedure TMySQL.GetQuery(InputQuery: TMyQuery;QueryString: String);
begin
InitQuery(InputQuery,QueryString);
InputQuery.Open;
end;
procedure TMySQL.GetQuery(InputQuery:TMyQuery; QueryString: String;ParameterList: TStringList);
begin
try
InputQuery.Connection:=Self.Connection;
if CheckParaEqual(QueryString,ParameterList) then
begin
InitParameter(InputQuery,QueryString,ParameterList);
InputQuery.Open;
end;
except
end;
end;
function TMySQL.GetTable: TMyTable;
begin
Result:=TMyTable.Create(nil);
end;
function TMySQL.GetTable(TableName: String): TMyTable;
var TempTable:TMyTable;
begin
TempTable:=TMyTable.Create(nil);
TempTable.Connection:=Self.Connection;
TempTable.TableName:=TableName;
Result:=TempTable;
end;
function TMySQL.GetTable(TableName: String;Connection: TMyConnection):TMyTable;
var TempTable:TMyTable;
begin
TempTable:=TMyTable.Create(nil);
TempTable.Connection:=Connection;
TempTable.TableName:=TableName;
Result:=TempTable;
end;
function TMySQL.GetExecuteScalar(QueryString: String): Variant;
var TempQuery:TMyQuery;
begin
try
TempQuery:=GetQuery;
InitQuery(TempQuery,QueryString);
TempQuery.Open;
Result:= TempQuery.Fields[0].Value;
finally
TempQuery.Free;
end;
end;
function TMySQL.GetExecuteScalar(QueryString: String; ParameterList: TStringList): Variant;
var tempQuery:TMyQuery;
begin
try
tempQuery:=GetQuery;
if CheckParaEqual(QueryString,ParameterList) then
begin
InitQuery(tempQuery,QueryString);
tempQuery.Open;
Result:=tempQuery.Fields[0].Value;
end;
finally
tempQuery.Free;
end;
end;
function TMySQL.GetParameteList: TStringList;
begin
Result:=TStringList.Create;
end;
function TMySQL.GetParameteList(ParameterString:string;SplitString: String=';'):TStringList;
var i:Integer;
tempstr:string;
tempres:TStringList;
begin
tempres:=TStringList.Create;
i:=Pos(SplitString,ParameterString);
while i<>0 do
begin
tempstr:=Copy(ParameterString,0,(i-1));
tempres.Add(tempstr);
Delete(ParameterString,1,i+length(SplitString)-1);
i:=Pos(SplitString,ParameterString);
end;
tempres.Add(ParameterString);
Result:=tempres;
end;
function TMySQL.BindList(QueryString: String;List:TStringList):TStringList;
var tempQuery:TMyQuery;
begin
try
tempQuery:=GetQuery;
InitQuery(tempQuery,QueryString);
tempQuery.Open;
tempQuery.First;
List.Clear;
while not tempQuery.Eof do
begin
if trim(VarToStr(tempQuery.Fields[0].Value))<>'' then
List.Add(tempQuery.Fields[0].Value);
tempQuery.Next;
end;
Result:=List;
finally
tempQuery.Free;
end;
end;
procedure TMySQL.BindComboBox(InputComboBox: TComboBox; QueryString: String);
var TempList:TStringList;
begin
TempList:=GetStringList;
BindList(QueryString,TempList);
AddToComboboxItem(InputComboBox,TempList);
TempList.Free;
end;
function TMySQL.CheckParaEqual(QueryString: String; ParameterList: TStringList):Boolean;
begin
Result:= (StrNum(':',QueryString)=ParameterList.Count);
end;
procedure TMySQL.InitQuery(InputQuery: TMyQuery; QueryString: String);
begin
if InputQuery.Connection=nil then
InputQuery.Connection:=Self.Connection;
InputQuery.SQL.Clear;
InputQuery.SQL.Add(QueryString);
end;
procedure TMySQL.GetTableNames(Connection: TMyConnection; List: TStringList);
begin
end;
procedure TMySQL.GetTableNames(List: TStringList);
begin
Self.Connection.GetTableNames(List);
end;
procedure TMySQL.GetFieldNames(TableName:string;List: TStringList);
begin
end;
procedure TMySQL.GetFieldNames(Connection: TMyConnection;TableName:string; List: TStringList);
begin
end;
function TMySQL.GetStringList: TStringList;
begin
Result:=TStringList.Create;
end;
function TMySQL.GetExecuteNoQuery(ExecuteSQL: String): Boolean;
var TempQuery:TMyQuery;
begin
try
try
TempQuery:=GetQuery;
InitQuery(TempQuery,ExecuteSQL);
TempQuery.Execute;
Result:=True;
except
Result:=False;
end;
finally
TempQuery.Free;
end;
end;
function TMySQL.GetExecuteNoQuery(ExecuteSQL: String;
ParameteList: TStringList): Boolean;
var TempQuery:TMyQuery;
begin
try
TempQuery:=GetQuery;
if CheckParaEqual(ExecuteSQL,ParameteList) then
begin
InitParameter(TempQuery,ExecuteSQL,ParameteList);
TempQuery.Execute;
Result:=True;
end else
begin
Result:=False;
ShowMessage('参数个数不一致');
end;
finally
TempQuery.Free;
ParameteList.Free;
end;
end;
procedure TMySQL.InitParameter(InputQuery: TMyQuery; QueryString: string;
ParameterList: TStringList);
var i:Integer;
begin
InitQuery(InputQuery,QueryString);
for i:=0 to ParameterList.Count-1 do
InputQuery.Params[i].Value:=ParameterList.Strings[i];
end;
function TMySQL.StrNum(ShortStr:string;LongString:string):Integer;
var
i:Integer;
begin
i:=0;
while pos(ShortStr,LongString)>0 do
begin
i:=i+1;
LongString:=StrSub(LongString,(StrFind(ShortStr,LongString))+1,Length(LongString)-StrFind(ShortStr,LongString))
end;
Result:=i;
end;
function TMySQL.StrSub(psInput:String; BeginPlace,CutLeng:Integer):String;
begin
Result:=Copy(psInput,BeginPlace,CutLeng)
end;
function TMySQL.StrFind(ShortStr:String;LongStrIng:String):Integer;
var
locality:integer;
begin
locality:=Pos(ShortStr,LongStrIng);
if locality=0 then
Result:=0
else
Result:=locality;
end;
procedure TMySQL.AddToComboboxItem(InputComboBox: TComboBox;
List: TStringList);
var i,j:Integer;
begin
InputComboBox.Items.Clear;
j:=List.Count-1;
for i:=0 to j do
InputComboBox.Items.Add(List.Strings[i]);
end;
function TMySQL.getBackupInSertSQL(Connection: TMyConnection;TableName: string;
InsertEachTime:Integer=1):TStringList;
var
MyTable: TMyTable;
TempString1, TempString2: string;
RecordCount, FieldCount: Integer;
i, j, k: Integer;
ResultStringList: TStringList;
tempstr: string;
begin
try
ResultStringList:=TStringList.Create;
MyTable:=TMyTable.Create(nil);
Connection.LoginPrompt:=False;
MyTable.Connection:=Connection;
MyTable.TableName:=TableName;
MyTable.Open;
RecordCount:=MyTable.RecordCount -1;
FieldCount:=MyTable.FieldCount-1;
MyTable.First;
j:=0;
TempString1:='';
for k:=0 to RecordCount do
begin
j:=j+1;
TempString2:='';
for i:=0 to FieldCount do
case MyTable.Fields[i].DataType of
ftString,ftWideString,ftMemo,ftFmtMemo :
begin
tempstr:= ( Mytable.Fields[i].AsString);
tempstr:=replace(tempstr,#13#10,'');
tempstr:=replace( tempstr,'''','');
TempString2:=TempString2+''''+ tempstr+''''+',';
end;
ftSmallint,ftInteger,ftWord,ftLargeint:
begin
TempString2:=TempString2+inttostr(MyTable.Fields[i].AsInteger)+',';
end;
ftBoolean:
begin
TempString2:=TempString2+ BoolToStr(MyTable.Fields[i].AsBoolean)+',';
end;
ftCurrency,ftBCD:
begin
TempString2:=TempString2+ CurrToStr(MyTable.Fields[i].AsCurrency)+',';
end;
ftFloat:
begin
TempString2:=TempString2+ FloatToStr(MyTable.Fields[i].AsFloat)+',';
end;
ftDate,ftDateTime:
begin
TempString2:=TempString2+ DateToStr(MyTable.Fields[i].AsDateTime)+',';
end;
ftUnknown:
begin
end;
ftAutoInc:
begin
end;
end;
TempString2:=Copy(TempString2,1,Length(TempString2)-1);
TempString1:=TempString1+'('+TempString2+'),'+#13#10;
if j=InsertEachTime then
begin
TempString1:=Copy(TempString1,1,Length(TempString1)-3);
TempString1:='INSERT INTO '+ TableName+ ' VALUES'+ TempString1+';';
ResultStringList.Add(TempString1);
j:=0;
TempString1:='';
end;
MyTable.Next;
end;
if Length( TempString1)>0 then
begin
TempString1:=Copy(TempString1,1,Length(TempString1)-3);
TempString1:='INSERT INTO '+ TableName+ ' VALUES'+ TempString1+';';
ResultStringList.Add(TempString1);
j:=0;
TempString1:='';
end;
Result:=ResultStringList;
finally
MyTable.Free;
end;
end;
function TMySQL.getBackupInSertSQL(QueryString: string;
InsertEachTime:Integer=1):TStringList;
var
TempQuery: TMyQuery;
TempString1, TempString2: string;
RecordCount, FieldCount: Integer;
i, j, k: Integer;
ResultStringList: TStringList;
tempstr: string;
fieldnames:string;
begin
try
ResultStringList:=TStringList.Create;
TempQuery:=TMyQuery.Create(nil);
Self.Connection.LoginPrompt:=False;
TempQuery.Connection:=Self.Connection;
TempQuery.SQL.Clear;
TempQuery.SQL.Add(QueryString);
TempQuery.Open;
for j:=0 to TempQuery.FieldCount-1 do
fieldnames:=fieldnames+ TempQuery.Fields[j].FieldName+',';
fieldnames:=Copy(fieldnames,0,Length(fieldnames)-1);
RecordCount:=TempQuery.RecordCount -1;
FieldCount:=TempQuery.FieldCount-1;
TempQuery.First;
j:=0;
TempString1:='';
for k:=0 to RecordCount do
begin
j:=j+1;
TempString2:='';
for i:=0 to FieldCount do
case TempQuery.Fields[i].DataType of
ftString,ftWideString,ftMemo,ftFmtMemo :
begin
tempstr:= ( TempQuery.Fields[i].AsString);
tempstr:=replace(tempstr,#13#10,'');
tempstr:=replace( tempstr,'''','');
TempString2:=TempString2+''''+ tempstr+''''+',';
end;
ftSmallint,ftInteger,ftWord,ftLargeint:
begin
TempString2:=TempString2+inttostr(TempQuery.Fields[i].AsInteger)+',';
end;
ftBoolean:
begin
TempString2:=TempString2+ BoolToStr(TempQuery.Fields[i].AsBoolean)+',';
end;
ftCurrency,ftBCD:
begin
TempString2:=TempString2+ CurrToStr(TempQuery.Fields[i].AsCurrency)+',';
end;
ftFloat:
begin
TempString2:=TempString2+ FloatToStr(TempQuery.Fields[i].AsFloat)+',';
end;
ftDate,ftDateTime:
begin
TempString2:=TempString2+ DateToStr(TempQuery.Fields[i].AsDateTime)+',';
end;
ftUnknown:
begin
end;
ftAutoInc:
begin
end;
end;
TempString2:=Copy(TempString2,1,Length(TempString2)-1);
TempString1:=TempString1+'('+TempString2+'),'+#13#10;
if j=InsertEachTime then
begin
TempString1:=Copy(TempString1,1,Length(TempString1)-3);
TempString1:='INSERT INTO '+ StrCut(QueryString,'from','where')+'('+ fieldnames+')' + ' VALUES'+ TempString1+';';
ResultStringList.Add(TempString1);
j:=0;
TempString1:='';
end;
TempQuery.Next;
end;
if Length( TempString1)>0 then
begin
TempString1:=Copy(TempString1,1,Length(TempString1)-3);
TempString1:='INSERT INTO '+ StrCut(QueryString,'from','where')+'('+ fieldnames+')' + ' VALUES'+ TempString1+';';
ResultStringList.Add(TempString1);
j:=0;
TempString1:='';
end;
Result:=ResultStringList;
finally
TempQuery.Free;
end;
end;
function TMySQL.replace(Source, Old, New: STRING): string;
var
p: Integer;
begin
WHILE POS( Old, Source ) <> 0 DO BEGIN
p := POS( Old, Source );
DELETE( Source, p, LENGTH( Old ) );
INSERT( New, Source, p );
END;
Result := Source;
end;
function TMySQL.StrCut(SourceString, BeginString,
EndString: WideString): WideString;
var beginPos,endPos:Integer;
begin
beginPos:=Pos(BeginString,SourceString);
endPos:=Pos(EndString,SourceString);
if (endPos=0) and (beginPos=0) then
Result:=''
else
if endPos=0 then
Result:=copy(SourceString,beginPos+ Length(BeginString), Length(SourceString)- beginPos- Length(BeginString)+1)
else if beginPos=0 then
Result:=Copy(SourceString,0,endPos)
else
Result:=copy(SourceString,beginPos+ Length(BeginString), endPos-beginpos- Length(BeginString));
Result:=Trim(Result);
end;
constructor TMySQL.Create(Server: string; Port: Integer; LoginName,
Password, Database: string;CharSet:string);
begin
try
Self.Connection:=TMyConnection.Create(Self);
Self.Connection.Server:=Server;
Self.Connection.Port:=Port;
Self.Connection.LoginPrompt:=False;
Self.Connection.Username:=LoginName;
Self.Connection.Password:=Password;
Self.Connection.Database:=Database;
Self.Connection.Options.Charset:=CharSet;
Self.Connection.Connected:=True;
Table:=TMyTable.Create(Self);
Query:=TMyQuery.Create(Self);
Table.Connection:=Self.Connection;
Query.Connection:=Self.Connection;
except
end;
end;
end.
