object-array-drills

exercises.js

@@ -1,3 +1,5 @@
+//ANSWERS ON LINE 187
+
 ////////////////////////////////////////////////
 // Part 1: Working With Data Structures
 ////////////////////////////////////////////////
@@ -162,3 +164,228 @@ const talkingHeadsAlbums = [
 //
 //    Warning: some albums have a property `.label`, which is a string, and some
 //    have `.labels`, which is an Array!
+
+
+
+
+////////////////////////////////////////////////
+// Part 1: Working With Data Structures
+////////////////////////////////////////////////
+
+const album1 = {
+  title: "Talking Heads",
+  albumDetails: {
+    released: new Date("September 16, 1977"),
+    label:    "Sire",
+    formats:  ["LP"]
+  }
+}  
+
+// 1. Retrieve the string "Sire" from album1, and save it in a sensibly named
+//    variable.
+
+//1. Answer:
+let label1 = album1.albumDetails.label
+console.log(album1.albumDetails.label)
+
+// 2. Change the title of album1 from "Talking Heads" to "Talking Heads: 77"
+
+//2. Answer:
+album1.title = "Talking Heads: 77"
+console.log(album1.title)
+
+const album2 = {
+  title: "More Songs About Buildings and Food",
+  albumDetails: {
+    released: new Date("July 14, 1978"),
+    label:    "Sire",
+    formats:  ["LP", "8-track"]
+  }
+}  
+
+const album3 = {
+  title: "Fear of Music",
+  albumDetails: {
+    released: "August 3, 1979",
+    label:    "Sire",
+    formats:  ["Cassette"]
+  }
+}  
+
+// 3. Access album2's formats array and use an array method to add "LP" to
+//    album3's formats
+// Check out the Array.push method!
+
+//3. Answer:
+album3.albumDetails.formats.push(album2.albumDetails.formats[0])
+console.log(album3)
+
+
+// 4. Change the release date of album3 from a string into a Date object
+// Look ahead to album4 for a clue!
+
+//4. Answer:
+album3.albumDetails.released = new Date(album3.albumDetails.released)
+console.log(album3)
+
+const album4 = {
+  title: "Remain in Light",
+  albumDetails: {
+    released: new Date("October 8, 1980"),
+    formats: ["Cassette", "LP"]
+  }
+}
+
+// 5. Add the label "Sire" to album4's details
+
+//5. Answer:
+album4.albumDetails.label = "Sire"
+console.log(album4)
+
+const album5 = {
+  title: "Speaking in Tongues",
+  albumDetails: {
+    released: new Date("May 31, 1983"),
+    label:    "Sire"
+  }
+}  
+
+// 6. Add a 'formats' array to album 5 and add "CD", "Cassette", and "LP"
+
+//6. Answer:
+console.log(album5.albumDetails.formats = ['CD', 'Cassette', 'LP'])
+
+
+const album6 = {
+  title: "Little Creatures",
+  albumDetails: {
+    released: new Date("June 10, 1985"),
+    labels:   ["Sire", "emi"],
+    formats:  ["CD", "cassette", "LP"]
+  }
+}  
+
+// 7. Make the label "emi" in album6 all uppercase
+// google how to make a string uppercase in js!
+
+//7. Answer:
+album6.albumDetails.labels[1] = album6.albumDetails.labels[1].toUpperCase()
+console.log(album6.albumDetails.labels[1])
+
+const album7 = {
+  title: "True Stories",
+  albumDetails: {
+    released: new Date("October 7, 1986"),
+    labels:   "Sire, EMI",
+    formats:  ["CD", "cassette", "LP"]
+  }
+}  
+
+// 8. Convert album7's 'labels' property from the string value
+//    "Sire, EMI" into the array: ["Sire", "EMI"]
+// google js array split!
+
+//8. Answer:
+album7.albumDetails.labels = album7.albumDetails.labels.split(", ")
+console.log(album7.albumDetails.labels)
+
+/////////////////////////////////////////////////////
+// Part 2: More Tasks About Datatypes and Structures
+/////////////////////////////////////////////////////
+
+const album8 = {
+  title: "Naked",
+  albumDetails: {
+    released: new Date("March 15, 1988"),
+    labels:    ["Sire", "EMI"],
+    formats:  ["CD", "cassette", "LP"]
+  }
+}  
+
+const talkingHeadsAlbums = [
+  album1,
+  album2,
+  album3,
+  album4,
+  album5,
+  album6,
+  album7,
+  album8
+]  
+
+// 1. Create an object literal called `band`.
+
+//1.Answer:
+const band = {}
+
+// 2. Give it the property `name` and set it to "Talking Heads"
+
+//2. Answer:
+const band = {
+  name: "Talking Heads"
+}
+
+// 3. Give it the property `members` and set it to an array with a single
+//    string, "David Byrne", in it.
+
+//3.Answer:
+const band = {
+  name: "Talking Heads",
+  members: ["David Byrne"]
+}
+
+// 4. Give it the property `albums` and set it to the array stored in the
+//    variable talkingHeadsAlbums
+
+//4. Answer:
+const band = {
+  name: "Talking Heads",
+  members: ["David Byrne"],
+  albums[talkingHeadsAlbums],
+}
+
+// 5. Add "Tiny Weymouth", "Chris Franz" and "Jerry Harrison" to the members
+//    array.
+
+  //5.Answer:
+  band.members.push("Tiny Weymouth", "Chris Franz", "Jerry Harrison")
+
+////////////////////////////////////////////////
+// Part 3: Conditional Logic
+////////////////////////////////////////////////
+
+// 1. Write a conditional to console.log "Talking Heads were a prolific band"
+//    if the Talking Heads have 6 albums or more. Otherwise, console.log
+//    "Talking heads didn't have much output." Use the array of albums
+//    talkingHeadsAlbums above.
+
+// 2. Write a conditional to check if the number of albums in
+//    talkingHeadsAlbums is odd or even, and then console.log
+//    "The number X is odd" or "The number X is even" with X being
+//    the number of albums.
+
+// 3. Write conditionals to check if the number of albums in
+//    talkingHeadsAlbums is divisible by either 2 or 3, and then
+//    console.log one of:
+//    - "The number Y is divisible by 2",
+//    - "The number Y is divisible by 3",
+//    - "The number Y is divisible by 2 and 3", or
+//    - "The number Y is not divisible by 2 or 3",
+//
+//    with Y being the number of albums.
+
+// 4. Check your logic above against the numbers: 0, 1, 2, 6, 7, and 9.
+//    Make sure it always works!
+
+/////////////////////////////////////////////////////
+// Part 4: For Loops
+/////////////////////////////////////////////////////
+
+// 1. Use a for loop to print out the name of each Talking Heads album
+
+// 2. Create a variable called `sireTally`, and set it to the integer value 0.
+//    Then use a for-loop to go through all the Talking Heads albums,
+//    incrementing sireTally if the album was released under the "Sire" label.
+//
+//    Warning: some albums have a property `.label`, which is a string, and some
+//    have `.labels`, which is an Array!