Sets or uses parameter information for a specific parameter based on its name.
function ParamByName(const Value: string): TDAParam;
Call the ParamByName method to set or use parameter information for a specific parameter based on its name. Name is the name of the parameter for which to retrieve information. ParamByName is used to set a parameter's value at runtime and returns a TDAParam object.
The following statement retrieves the current value of a parameter called "Contact" into an edit box:
Edit1.Text := Query1.ParamsByName('Contact').AsString;