CYQ.Data lightweight way to use the data layer of articles two MAction Data Query (13)

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Introduction Description:

Benpian continue on the piece of content, this section describes the use of all related queries.

Main Summary:
1: single data manipulation operations GetCount Fill operation.
2: Select multiple rows of data manipulation operations
3: List-bound controls operate with paging controls
4: multi-table queries and bind the views and custom SQL

Single-line data manipulation

A: Fill filling method, single-row query

Methods prototype: public BOOL the Fill ( Object the WHERE )

Example 1: Direct ID

Action MAction = new new MAction (TableNames.Users); IF (action.Fill ( 888 )) // query ID = single row of data 888 { action.SetTo (lblUserName); action.Close (); }

Example 2: where transmission conditions

Action MAction = new new MAction (TableNames.Users); IF (action.Fill ( " ID = 888 or UserName = 'passing through the autumn'")) // query name or user ID = 888 " passing autumn " one-line data { Action .SetTo (lblUserName); action.Close (); }

Example 3: where conditions attached order by

Action MAction = new new MAction (TableNames.Users); IF (action.Fill ( " ID> 888 by ID desc Order " )) // query ID> ID take maximum results in the single row of data 888 { action.SetTo (lblUserName ); action.Close (); }

Two: GetCount take the total number of statistics

Methods Prototype: public int GetCount ( String the WHERE )

Example 1:

MAction action = new MAction(TableNames.Users);
int count = action.GetCount( " id>10 " );
action.Close();

Multiple rows of data operations

Three: Select multiple data query

方法原形：
1 ： public MDataTable Select()
2 ： public MDataTable Select( int PageIndex, int PageSize, string Where, out int RowCount)

Example 1:

Action MAction = new new MAction (TableNames.Users); MDataTable tabme = action.Select (); // query all data action.Close ();

Example 2:

int COUNT; // this is the total number of records returned MAction Action = new new MAction (TableNames.Users); MDataTable tabme = action.Select ( 1 , 10 , " the above mentioned id> 10 username desc by the Order " , OUT COUNT); // Query id> 10 records 10 [page 1, page 10 of data, the results of sorting by usename] action.Close ();

Additional information:

Select Selects all the data, the internal principle methods:
public MDataTable Select ()
{
int COUNT;
return Select ( 0 , 0 , "" , OUT COUNT);
}

List bind operation

Four: Bind GridView / DataList / Repeater

Example 1: All direct binding inquiry

MAction action = new MAction(TableNames.Users);
MDataTable table = action.Select();
action.Close();
gvUsers.DataSource = table;
gvUsers.DataBind();

Example 2: with pagination controls combat Post article pagination controls bind [Download: CYQ.Data road data layer of lightweight bug feedback, optimization tips, download the latest frame ]

public void BindData()
{
         int count;
        MAction action = new MAction(TableNames.Users);
        MDataTable table = action.Select(Pager1.PageIndex,Pager1.PageSize, " id>10 " , out count);
        action.Close();
        gvUsers.DataSource = table;
        gvUsers.DataBind();
        Pager1.Count = count; // 设置记录总数
        Pager1.BindName = " BindData " ; // 绑定方法名称
}

Example 3: Get with the other way paging controls bind

Description:

If you use the paging controls are more complex than the above usage, you can consider optimizing or abandoned the original paging controls.

Multi-table queries and bind

Five: View mode

Example 1: Table and operate the same, the only difference is the name of the table name into view

public void BindData()
{
         int count;
        MAction action = new MAction(ViewNames.V_Users);
        MDataTable table = action.Select(Pager1.PageIndex,Pager1.PageSize, " id>10 " , out count);
        action.Close();
        gvUsers.DataSource = table;
        gvUsers.DataBind();
        Pager1.Count = count;
        Pager1.BindName = " BindData " ;
}

Six: Customize multi-table structure SQL statements

Example 1:

public void BindData()
{
       string customTable = " (select u.*,m.Body from Users u left join Message m on u.ID=m.UserID) v " ;
       int count;
      MAction action = new MAction(customTable);
      MDataTable table = action.Select(Pager1.PageIndex,Pager1.PageSize, " id>10 " , out count);
      action.Close();
      gvUsers.DataSource = table;
      gvUsers.DataBind();
      Pager1.Count = count;
      Pager1.BindName = " BindData " ;
}

Description:

In the specific use, in order to facilitate management, directly in a custom SQL statement is not so write directly in the interface, you can build a new term project management unified custom SQL.

Knot words:

After reading Benpian example, a query for this one should understand. The tie from the paging controls together to achieve is very simple.

Please use one other concern: undetermined name.

Reproduced in: https: //my.oschina.net/secyaher/blog/274074

CYQ.Data lightweight way to use the data layer of articles two MAction Data Query (13)

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