tree view problem

uppower

If there are two well-known Chinese universities and world-famous universities under the tree view tree, I want to achieve a click on the famous Chinese university or world-famous university in the tree view (the database contains two records, one is a famous Chinese university and one is World-renowned universities), the relevant information is displayed in dbgridedit1 on the right. I wonder how to write the code? ? ? ?

stevevai

Is it dBgird or DBedit, this is a data-aware control
If you have to be DBEdit, here's how:
This must require you to open a dataset component, such as: adoDataSet
Then your tree treeview is not a data-aware control, but you can bind to the node of the tree through locate. The bound flag must be a key field. In this way, each time you click on a node in the tree, you can quickly locate the record.
But these DBeidt must be connected to the data set components.

stevevai

If the related information queried is multiple records, you must display it with DBgrid.
In this case, locate is not suitable.
Then you must first load all the data into the adodataset (considering speed, not considering capacity), and then pass
ADODataSet1.Filter: = 'Query field name =' '' + TreeView1.Selected.Text + '' '';
ADODataSet1.Filtered: = true; so the DBgrid connected to ADOdataset1 will display the information you need

What needs to be declared here is not to write under the TVGetSelectedIndex event of treeview1, this will make your filter query run endlessly

tonnywoo

procedure TForm1.TreeView1Change (Sender: TObject; Node: TTreeNode);
 var A: STRING;
begin
  A: = trim (NODE.Text); // NODE.Text is the value of the node in the point

 ADOQUERY1.CLOSE;
 ADOQUERY1.SQL.CLEAR;
 ADOQUERY1.SQL.ADD (SELECT * FROM TABLE1 WHERE Famous University =: AA);
 ADOQUERY1.Parameters.ParamByName ('AA'). Value: = A;
ADOQUERY1.OPEN;

end;
At this point, if ADOQUERY is connected to the display control on the right, it will be displayed.

suyongyu

Thanks for sharing