Canards are an early 1900 concept.
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Saab 37 vigen i suppose was the first operational fight with the canard design in the late 60s & early 70s.
So there is nothing magic in canard design. Nor its a magic wand or a technology which is rare.
had JF-17 been wanted as a canard design, it would have been done, but since there was no requirement, nothing happened in that regard.
JF-17 was never in competition with the J-10, at any stage had the Chinese thought it is a threat to J-10 export prospects, Chinese would have stopped the project or would not present it for export. JF-17 is a light end fighter no matter what the design preference had been, while J-10 is a superior class medium end fighter.
JF-17 is cheap 15-20M $$ aircraft and comes with a punch in its own class, J-10 is a medium level 35-45M aircraft which has its own punch and both are not comparable, many technologies may be same in both the aircraft, but still they are different and not a threat to each other.
JF-17 will be bought by countries which can't buy high end aircraft like J-10s and whose requirements can be met with JF-17, while J-10 will be bought by countries who can afford and whose requirements are fulfilled by it.
And there are good chances that JF-17 in shape of FC-1 might get inducted in CAF, but Chinese engine is must for that to happen. FC-1 being tested rigorously along J-10B and J-20 at the same airfield might give an indication that it may have a chance for the CAF.