How to create a simple lookup in x++

The SysTableLookup class is provided by the standard application to allow programmers to easily create their own lookup forms, in code.

The basic steps to using this class are as follows:

Create the sysTableLookup object

Create the query to select the lookup data

Add  the fields shown on the lookup

Performs the lookup

client static void lookup<TableName> (FormStringControl _ctrl)

{

    SysTableLookup          sysTableLookup       =  SysTableLookup::newParameters(tableNum(<tableName>),_ctrl);

    Query                   query                = new Query();

    // create the query for the lookup

    QueryBuildDataSource    queryBuildDataSource = query.addDataSource(tableNum(<tableName>));

    // Add fields that will be shown in the lookup as columns        

    sysTableLookup.addLookupfield(fieldNum(<tableName>,<FeildName1>));

    sysTableLookup.addLookupfield(fieldNum(<tableName>,<FeildName2>));

    //Add the query to the lookup form

    sysTableLookup.parmQuery(query);

    // Perform the lookup

    sysTableLookup.performFormLookup();

}

This above method of lookup was heavily used in AX 2009, and it also used in the AX 2012 when there isn’t any data source specified in the form (i.e. Dialog Form) and the StringEdit control used for the lookup

How to create a simple lookup Reference

 The SysReferenceTableLookup class is used to construct lookup forms for reference controls.

Create the SysReferenceTableLookup object

Create the query which will be used to select the lookup data

Add the fields which will be shown on the lookup

Perform the lookup 

This method is now the standard method used to lookup the data for drop down when there is any modification needed to override the behavior of the functionality provided by the automatic lookup

public static client <tableName> lookup<tableName>(

    FormReferenceControl        _formReferenceControl)

{

    Query                   query;

    SysReferenceTableLookup referenceLookup;

    if (_formReferenceControl == null)

    {

        throw error(Error::missingParameter(null));

    }

    referenceLookup = SysReferenceTableLookup::newParameters(

        tableNum(<tableName>),

        _formReferenceControl,

        true);

    // create the query for the lookup form

     query.addDataSource(tableNum(<tableName>));

    // Add fields that will be shown in the lookup form as columns

    referenceLookup.addLookupfield(fieldNum(<tableName>,<FeildName1>));

    referenceLookup.addLookupfield(fieldNum(<tableName>,<FeildName2>));

    // Add the query to the lookup form

    referenceLookup.parmQuery(query);

    // Perform the lookup and return the selected record

    return referenceLookup.performFormLookup() as <tableName>;

}