1 00:00:00,670 --> 00:00:04,710 Let's see how we can attract over an array. 2 00:00:04,720 --> 00:00:10,540 Meaning, how can we get the individual records in this array separately? 3 00:00:10,570 --> 00:00:11,620 So let's get started. 4 00:00:11,620 --> 00:00:17,440 So let me comment out these ones and then I may bring up bring out my book here. 5 00:00:17,470 --> 00:00:18,910 Let me comment that one. 6 00:00:18,910 --> 00:00:22,810 And then going to place the arrays here because I'm going to work on it. 7 00:00:22,900 --> 00:00:28,540 So here is going to be going to be as what? 8 00:00:30,070 --> 00:00:31,360 I'd written. 9 00:00:32,350 --> 00:00:33,220 Over. 10 00:00:33,860 --> 00:00:35,480 And every. 11 00:00:37,270 --> 00:00:40,720 Meaning, how can we get an individual cross in the area? 12 00:00:40,750 --> 00:00:46,840 And remember, we have couple of ways of doing it, but because we have been talking about I mean, 13 00:00:46,840 --> 00:00:53,950 a lot of the the looping techniques like for each map and you talked about so far the for loop. 14 00:00:54,100 --> 00:01:01,030 So let's use for a loop to loop through this record and get it individual I mean, data in this particular 15 00:01:01,030 --> 00:01:01,600 area. 16 00:01:01,630 --> 00:01:03,220 So here we go. 17 00:01:03,460 --> 00:01:12,910 So I'll make use of four and then I will say let's initial value I suppose to be zero and my semicolon 18 00:01:12,910 --> 00:01:13,720 like that. 19 00:01:13,720 --> 00:01:17,140 So if I is less than what. 20 00:01:17,170 --> 00:01:21,730 Here is a clue when we say when I is less than two. 21 00:01:21,940 --> 00:01:23,860 Let's try this one for see. 22 00:01:24,070 --> 00:01:28,300 Then I want to increase I plus plus. 23 00:01:28,300 --> 00:01:39,160 In that way I can go ahead and then console dot log console log the I this a normal loop. 24 00:01:39,190 --> 00:01:41,050 Okay, so let me save it and let's see. 25 00:01:41,590 --> 00:01:44,680 Okay, I get some syntax error here. 26 00:01:45,040 --> 00:01:55,090 So for four left I equal to zero and then I might be less than two A's I plus plus. 27 00:01:55,090 --> 00:01:56,610 Not one plus plus. 28 00:01:56,620 --> 00:01:58,990 Yes, you could say that. 29 00:01:59,290 --> 00:02:00,460 We got what. 30 00:02:01,320 --> 00:02:11,790 Zero and one, because here the starting point is zero, meaning that if I is less than two, then the 31 00:02:11,790 --> 00:02:18,380 loop will go for the first time and then it will display the I, which is zero here. 32 00:02:18,390 --> 00:02:19,920 Then we got it here. 33 00:02:20,220 --> 00:02:29,010 Then on the second loop because we have increased ie here behind the scene, I has become one here so 34 00:02:29,010 --> 00:02:31,500 it's going to loop again. 35 00:02:31,710 --> 00:02:38,730 Now the ie this one has become what has become to add a third loop, right? 36 00:02:38,730 --> 00:02:42,690 So the third loop, this one is two. 37 00:02:43,610 --> 00:02:45,110 Is two less than two? 38 00:02:45,210 --> 00:02:48,210 No, there is two or equal to two. 39 00:02:48,230 --> 00:02:49,640 So the loop will stop. 40 00:02:50,000 --> 00:03:00,770 So if I want to get the record here, remember that we use the index of the array to get the record 41 00:03:00,770 --> 00:03:01,190 from it. 42 00:03:01,190 --> 00:03:09,260 And here we are able to get the first index, which is zero, meaning that I can get this one and then 43 00:03:09,260 --> 00:03:12,320 I can get this one using this dynamic. 44 00:03:12,320 --> 00:03:14,450 Sorry, this one rather. 45 00:03:14,480 --> 00:03:15,590 I made a mistake. 46 00:03:15,650 --> 00:03:17,630 The first one is this one. 47 00:03:17,630 --> 00:03:22,610 The first one I can get the index zero and the second one I can get this one. 48 00:03:22,610 --> 00:03:23,810 So what about this one? 49 00:03:24,300 --> 00:03:28,820 Okay, so with this one, let's try to get the record inside here. 50 00:03:28,880 --> 00:03:35,060 So we are going to take the array here, the array. 51 00:03:35,180 --> 00:03:37,310 So I would take the books array. 52 00:03:37,340 --> 00:03:44,930 Then if I try to say I want the first zero here, let's console.log, that let's console.log, or we 53 00:03:44,930 --> 00:03:49,430 can assign to a variable core as array like that. 54 00:03:49,460 --> 00:03:54,740 Then I can console that, log the array like that. 55 00:03:54,740 --> 00:03:59,450 So you see that I get MongoDB that has appeared two times. 56 00:03:59,450 --> 00:04:06,770 We have X or K two time because the loop has I mean go over to times and we have two times over here. 57 00:04:06,980 --> 00:04:13,190 So what about I want this one more dynamic, not always passing in this, but instead I want to get 58 00:04:13,190 --> 00:04:15,950 the values from the loop and pass in here. 59 00:04:16,519 --> 00:04:21,390 So if I pass in, I hear this, I can be zero or one. 60 00:04:21,470 --> 00:04:25,940 Okay, so if I save it, let's check out if I save this one. 61 00:04:26,330 --> 00:04:33,050 Now I have got the variables, the data inside my array as MongoDB and Node.js. 62 00:04:33,140 --> 00:04:34,340 But what about this one? 63 00:04:34,340 --> 00:04:39,440 The rest of the React and then JavaScript here they react also here. 64 00:04:39,470 --> 00:04:43,460 So because we don't know for the meantime, you can count. 65 00:04:43,460 --> 00:04:46,430 Okay, we have zero one, two, three. 66 00:04:46,430 --> 00:04:48,470 So here you can see that three here. 67 00:04:49,010 --> 00:04:51,470 Now we get new. 68 00:04:51,890 --> 00:04:54,080 We get all the sorry guys. 69 00:04:54,860 --> 00:04:59,120 Now you got the all the record that has been displayed. 70 00:04:59,210 --> 00:05:01,190 What about in future? 71 00:05:01,220 --> 00:05:08,240 If we update this particular array and app, let's say I want add a main to it. 72 00:05:09,150 --> 00:05:10,320 Unless I come back. 73 00:05:10,560 --> 00:05:13,830 I didn't get a table here because here is less than three. 74 00:05:14,330 --> 00:05:14,870 Okay. 75 00:05:14,880 --> 00:05:21,750 So in the future, let's say we've added this one unless I come again to my loop here and then say, 76 00:05:21,750 --> 00:05:24,910 oh, now we have one, one, two, three, four. 77 00:05:24,930 --> 00:05:25,890 So how to make here? 78 00:05:25,890 --> 00:05:29,580 As for you see, we are making our life difficult. 79 00:05:29,670 --> 00:05:36,060 So let's make this value dynamic by getting the length of this. 80 00:05:36,180 --> 00:05:43,560 We haven't talked about how to get the total length of setting array, but we have a method called length, 81 00:05:43,560 --> 00:05:50,550 meaning that if you if you want to get a total length of this book here for the meantime, let me comment 82 00:05:50,550 --> 00:05:51,600 out this one. 83 00:05:52,020 --> 00:05:55,530 And now I want to know how many records are in this array. 84 00:05:55,530 --> 00:06:02,250 So here, I mean, check for how many. 85 00:06:04,720 --> 00:06:07,800 Real costs in this area. 86 00:06:08,820 --> 00:06:11,580 And we have a method for that. 87 00:06:11,580 --> 00:06:13,500 And we dive in more about three methods. 88 00:06:13,500 --> 00:06:15,420 For the meantime, let's solve this one. 89 00:06:15,510 --> 00:06:22,230 So we have, let's say, cons as to water to water record. 90 00:06:23,020 --> 00:06:24,210 Is equal to. 91 00:06:24,220 --> 00:06:27,900 I would take the books and on that half length. 92 00:06:28,930 --> 00:06:35,350 So if I console.log the the total record. 93 00:06:35,380 --> 00:06:39,370 Are we able to know I have four records in the array. 94 00:06:39,640 --> 00:06:42,230 One, two, three, four, go. 95 00:06:42,250 --> 00:06:49,240 So now if I add a record to it, let's say six and I save it, you see that I got five. 96 00:06:49,510 --> 00:06:56,890 So we are going to use this technique here inside our for loop so that it can be dynamic. 97 00:06:57,070 --> 00:07:02,140 So now coming back here, let me remove this one and now let me uncomment this one. 98 00:07:02,260 --> 00:07:06,370 So here is going to be the total record here. 99 00:07:06,730 --> 00:07:07,710 Like this one. 100 00:07:07,720 --> 00:07:11,120 So if I save it, you see that I get all the record. 101 00:07:11,140 --> 00:07:20,380 So in future, if I add in the record, whatever, let's say what books I add into it, let's say I 102 00:07:20,380 --> 00:07:23,800 want to add Angular. 103 00:07:24,760 --> 00:07:27,790 Now I get Angular being displayed. 104 00:07:27,790 --> 00:07:29,530 So this is more dynamic. 105 00:07:29,890 --> 00:07:37,510 So but by convention, we normally write everything in line than this one as a variable. 106 00:07:37,540 --> 00:07:43,360 Get a lamp and a reference ID here so we can quickly do it in line as books dot length. 107 00:07:43,720 --> 00:07:44,750 Yes, it is shorter. 108 00:07:44,770 --> 00:07:46,600 It is easier like that. 109 00:07:46,600 --> 00:07:52,060 So it is how we are able to look through an array and get a record in it. 110 00:07:52,210 --> 00:08:01,240 The next video we will talk about some of the array methods and then after that we will start with our 111 00:08:01,240 --> 00:08:02,860 coding challenge.