OC 7-day container type lesson7

Common nsarray Methods

1. Create an array object and use the initialization method or constructor.

<Span style = "font-size: 18px;"> nsarray * arr1 = [[nsarray alloc] initwithobjects: @ "Wang Chen", @ "Liu Guowei ", @ "Zheng haikun", nil]; nsarray * arr2 = [nsarray arraywithobjects: @ "Li Zhi", @ "Wei David", @ "Liu tianwei", nil]; nsarray * arr3 = [nsarray arraywitharray: arr1]; nslog (@ "% @ \ n", arr1, arr2, arr3); </span>

Running result:

19:29:06. 750 oc07 _ container class [5676: 303] (

"\ U738b \ u6668 ",

"\ U5218 \ u56fd \ u4f1f ",

"\ U90d1 \ u6d77 \ u5764"

)

(

"\ U674e \ u667a ",

"\ U9b4f \ u5927 \ u536b ",

"\ U5218 \ u5929 \ u4f1f"

)

(

"\ U738b \ u6668 ",

"\ U5218 \ u56fd \ u4f1f ",

"\ U90d1 \ u6d77 \ u5764"

)

2. Obtain the number of elements.

<span style="font-size:18px;"><span style="white-space:pre"></span>for (int i = 0; i < [arr1 count]; i++) {</span>

3. Obtain the object based on the index value.

<span style="font-size:18px;">        NSLog(@"%@",[arr1 objectAtIndex:i]);        NSLog(@"%@", arr1[i]);        }</span>

Running result:

19:29:06. 752 oc07 _ container class [5676: 303] Wang Chen

19:29:06. 752 oc07 _ container class [5676: 303] Wang Chen

19:29:06. 752 oc07 _ container class [5676: 303] Liu Guowei

19:29:06. 753 oc07 _ container class [5676: 303] Liu Guowei

19:29:06. 753 oc07 _ container class [5676: 303] Zheng haikun

19:29:06. 754 oc07 _ container class [5676: 303] Zheng haikun

4. Obtain the index value of an object in the array.

<Span style = "font-size: 18px;"> <span style = "white-space: pre"> </span> nslog (@ "% lu ", [arr1 indexofobject: @ "Wang Chen"]); </span>

Running result:

19:29:06. 754 oc07 _ container class [5676: 303] 0

Common nsmutablearray Methods

1. Create an array object.

<span style="font-size:18px;"><span style="white-space:pre"></span>NSMutableArray * mutArry1 = [NSMutableArray arrayWithArray:arr1];</span>

2. Add and insert elements.

<Span style = "font-size: 18px;"> [mutarry1 addobject: @ "Chen jiahong"]; // Add [mutarry1 addobjectsfromarray: arr2]; nsstring * temp = @ "woca"; [mutarry1 insertobject: temp atindex: 4]; // insert for (INT I = 0; I <[mutarry1 count]; I ++) {nslog (@ "% @", mutarry1 [I]) ;}</span>

Running result:

20:23:31. 004 oc07 _ container class [6755: 303] Wang Chen

20:23:31. 004 oc07 _ container class [6755: 303] Liu Guowei

20:23:31. 005 oc07 _ container class [6755: 303] Zheng haikun

20:23:31. 005 oc07 _ container class [6755: 303] Chen jiahong

20:23:31. 005 oc07 _ container class [6755: 303] woca

20:23:31. 006 oc07 _ container class [6755: 303] Li Zhi

20:23:31. 006 oc07 _ container class [6755: 303] Wei David

20:23:31. 007 oc07 _ container class [6755: 303] Liu tianwei

Nested traversal of Arrays:

<Span style = "font-size: 18px;"> nsmutablearray * class19 = [nsmutablearray arraywithobjects: arr1, arr2, arr3, nil]; // method 1 for (INT I = 0; I <[class19 count]; I ++) {for (Int J = 9; j <[class19 [I] Count]; j ++) {nslog (@ "% @", class19 [I] [J]) ;}// method 2 for (INT I = 0; I <[class19 count]; I ++) {for (Int J = 0; j <[class19 objectatindex: I] Count]; j ++) {nslog (@ "% @", [[class19 objectatindex: I] objectatindex: J]) ;}// method 3 for (INT I = 0; I <[class19 count]; I ++) {nsarray * arr = [class19 objectatindex: I]; for (Int J = 0; j <[arr count]; j ++) {nslog (@ "% @", arr [J]) ;}</span>

3. Delete and replace elements.

<Span style = "font-size: 18px;"> [mutarry1 removelastobject]; [mutarry1 removeobject: @ "Liu tianwei"]; // Replace [mutarry1 replaceobjectatindex: 5 withobject: @ ""]; for (INT I = 0; I <[mutarry1 count]; I ++) {nslog (@ "% @", mutarry1 [I]) ;}</span>

Running result:

20:28:01. 038 oc07 _ container class [6782: 303] Wang Chen

20:28:01. 038 oc07 _ container class [6782: 303] Liu Guowei

20:28:01. 039 oc07 _ container class [6782: 303] Zheng haikun

20:28:01. 039 oc07 _ container class [6782: 303] Chen jiahong

20:28:01. 039 oc07 _ container class [6782: 303] woca

20:28:01. 040 oc07 _ container class [6782: 303] Prince Jie

20:28:01. 040 oc07 _ container class [6782: 303] Wei David

4. Swap two elements at the specified position.

<span style="font-size:18px;">        [mutArry1 exchangeObjectAtIndex:4 withObjectAtIndex:5];        for (int i = 0; i < [mutArry1 count]; i++) {            NSLog(@"%@",mutArry1[i]);        }</span>

About sorting:

<span style="font-size:18px;">NSMutableArray *aryNum = [NSMutableArray arrayWithObjects:@"3", @"7", @"9", @"1", @"5", nil];</span>

Bubble Method:

<span style="font-size:18px;">        int flag = 1;        for (int i = 0; i < [aryNum count ] - 1 && 1 == flag; i++) {            flag = 0;            for (int j = 0; j < [aryNum count] - i - 1; j++) {                if ([aryNum[j] compare: aryNum[j + 1]] == 1) {                    [aryNum exchangeObjectAtIndex:j withObjectAtIndex:j + 1];                    flag = 1;                }            }        }        for (int i = 0; i < [aryNum count]; i++) {            NSLog(@"%@",aryNum[i]);        }</span>

<Span style = "font-size: 18px;"> 1. variable array sorting method [arynum sortusingselector: @ selector (compare :)]; 2. the sorting method of an unchangeable array is arynum = (nsarray *) [arynum sortedarrayusingselector: @ selector (compare :)]; </span>

Common nsnumber Methods

<Span style = "font-size: 18px;"> // 1. create a numeric object of each type // (1) integer nsnumber * n1 = [nsnumber numberwithint: 43]; // (2) floating point (single precision) nsnumber * n2 = [nsnumber numberwithfloat: 3.14]; // (3) floating point (Double Precision) nsnumber * N3 = [nsnumber numberwithdouble: 65.1131313123123123123]; // (4) Long Integer nsnumber * N4 = [nsnumber numberwithlong: 987654321]; // (5) converted nsnumber * N5 = [nsnumber numberwithchar: 'a']; </span>

Common nsmutablearray Methods

<span style="font-size:18px;">        NSMutableArray *arrNum = [NSMutableArray arrayWithObjects:n1, n2, n3, n4, n5, nil];        NSLog(@"%@",arrNum);</span>

Running result:

20:28:01. 044 oc07 _ container class [6782: 303] (

43,

"3.14 ",

"65.11313131231232 ",

987654321,

65

)

Sort arrnum:

<span style="font-size:18px;">        [arrNum sortUsingSelector:@selector(compare:)];        NSLog(@"%@",arrNum);</span>

Running result:

20:28:01. 045 oc07 _ container class [6782: 303] (

"3.14 ",

43,

65,

"65.11313131231232 ",

987654321

)

Traverse arrnum

        for (int i = 0; i < [arrNum count]; i++) {            double d = [arrNum[i] doubleValue];            NSLog(@"%.9f",d);        }

Running result:

20:28:01. 045 oc07 _ container class [6782: 303] 3.140000105

20:28:01. 045 oc07 _ container class [6782: 303] 43.000000000

20:28:01. 046 oc07 _ container class [6782: 303] 65.000000000

20:28:01. 046 oc07 _ container class [6782: 303] 65.113131312

20:28:01. 047 oc07 _ container class [6782: 303] 987654321.000000000

OC 7-day container type lesson7