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>Chapter 4. Show data of a column</H1
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> Now we try to show data of a specific column. For this we get a hk_column object. hk_column represents a specific column of a datasource.
To display the data of the actual row use the command mycolumn->asstring().
The hk_datasource::column_by_name method allows you to select a
column by it's name.</P
><P
>When you enable a datasource the row selector is in row 0 (the first row). To move the row selector use one of the
hk_datasource methods:
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> 1 #include <hk_classes.h>
2 #include <iostream>
3 int main()
4 {
5 hk_drivermanager* mydrivermanager = new hk_drivermanager();
6 if (mydrivermanager==NULL) {cout <<"error creating mydrivermanager"<<endl;exit(1);}
7 hk_connection* myconnection = mydrivermanager->new_connection("mysql");
8 if (myconnection==NULL) {cout <<"error creating myconnection"<<endl;exit(1);}
9 myconnection->set_host("localhost");
10 myconnection->set_user("root");
11 myconnection->set_password("mypasswd");
12 myconnection->connect();
13
14 hk_database* mydatabase=myconnection->new_database("exampledb");
15 if (mydatabase==NULL) {cout <<"error creating mydatabase"<<endl;exit(1);}
16 hk_datasource* mydatasource= mydatabase->new_table("authors");
17 if (mydatasource==NULL) {cout <<"error creating mydatasource"<<endl;exit(1);}
18 mydatasource->enable();
19
20 <FONT
COLOR="RED"
>hk_column* mycolumn = mydatasource->column_by_name("name");</FONT
>
21 <FONT
COLOR="RED"
>if (mycolumn==NULL) {cout <<"error getting column"<<endl;exit(1);}</FONT
>
22 <FONT
COLOR="RED"
>cout <<"Value of the first row: "<<mycolumn->asstring()<<endl;</FONT
>
23 <FONT
COLOR="RED"
>mydatasource->goto_next();</FONT
>
24 <FONT
COLOR="RED"
>cout <<"Value of the second row: "<<mycolumn->asstring()<<endl;</FONT
>
25
26 delete mydrivermanager;
27 }</PRE
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