Hey there! I had already signed off last night when you asked about dog parks in Chandler, sorry!
There are a few ok parks- Kyrene north of the 202, and Alma School south of Ocotillo are 2 I know of (I think there might be more). BUT, the best park ever is in Gilbert, at Ray and the 202 (just east of Higley). It's called Cosmo's Park, and it's amazing! There are 3 seperate areas- 1 for small dogs (although my Doxie doesn't like it, he thinks he is a big dog), 1 "dry" park with obsticals, and 1 "wet" park with a huge pond, beach entry and diving platform. The park is always busy, but people are really nice and respectful. The dry and wet parks are huge- together they probably cover a football field, and there is shaded covering and picnic benches as well. You definately have to check it out!