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JavaScript

practicing Objects

This is some code from the practicing Objects video, the teacher wrote the first function that iterates over a two dimensional array I wondered if mine will do the same thing as hers?

    drawHTMLBoard() {
    for (let column of this.spaces) {
      for(let space of column) {
         space.drawSVGSpace();
      }
    }
    }



/*
   Altenate code dor drawHTMLBoard()
     // need a double for loop to go through the 2D array

    drawHTMLBoard() {
     for(let i= 0; i< this.spaces.length; i++) {
       for(j = 0; j < this.spaces[i][j].length; j++){
         this.spaces[i][j].drawSVGSpace();

       }
     }
  }
*/

1 Answer

Steven Parker
Steven Parker
229,005 Points

You're close, but I see two issues:

  • to avoid implicit declaration of a global, add "let" to the 2nd loop
  • use only one index to access the length for the 2nd loop
       for(j = 0; j < this.spaces[i][j].length; j++){    // original
       for(let j = 0; j < this.spaces[i].length; j++) {  // fixed