string [,] vList = {

   { "a1" , "b1" , "c1" , "d1" },

   { "a2" , "b2" , "c2" , "d2" },

   { "a3" , "b3" , "c3" , "d3" } };

int [] vIndexs = new int [vList . GetLength( 1 )];

for ( int k = 0 ; k < vList . GetLength( 1 ); k ++ )

   vIndexs[k] = 0 ;

bool vBreak = false ;

do

{

    for ( int j = 0 ; j < vList . GetLength( 1 ); j ++ )

       textBox1 . AppendText(vList[vIndexs[j], j]);

   textBox1 . AppendText( "\r\n" );

   vBreak = true ;

    for ( int j = 0 ; j < vList . GetLength( 1 ); j ++ )

        if (vIndexs[j] + 1 < vList . GetLength( 0 ))

       {

           vIndexs[j] ++ ;

            for ( int i = 0 ; i < j; i ++ ) vIndexs[i] = 0 ;

           vBreak = false ;

            break ;

       }

}

while ( ! vBreak);

---------

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