OC's Seventh-Day dictionary lesson7

Common nsdictionary Methods

Nsdictionary is used to save data with ing relationships. Therefore, the nsdictionary set stores two sets of values:

A group of keys used to save the nsdictionary

Another group is used to save the value in nsdictionary.

Key and value can be any data of reference type, and one-to-one relationship exists between key and value. (Duplicate keys are not allowed)

1. Create a dictionary object;

Nsdictionary * dicyaoge = [nsdictionary dictionarywithobjectsandkeys: @ "Yao ge", @ "name ",@"? ", @" Sex ", @" 18 ", @" Age ", @" 105 ", @" weight ", nil]; nslog (@" % @", dicyaoge );

Note: This statement is more anti-virus. value is in the front and key is in the back.

Running result:

20:47:06. 329 oc07 _ dictionary [6837: 303] {

Age = 18;

Name = "\ u7476 \ u54e5 ";

Sex = "? ";

Weight = 105;

}

2. Get all key values

        NSLog(@"%@", [dicYaoGe allKeys]);

Running result:

20:47:06. 473 oc07 _ dictionary [6837: 303] (

Age,

Sex,

Weight,

Name

)

3. Get all value values

 NSLog(@"%@", [dicYaoGe allValues]);

Running result:

20:47:06. 474 oc07 _ dictionary [6837: 303] (

18,

"? ",

105,

"\ U7476 \ u54e5"

)

4. query value by key value

<span style="white-space:pre"></span>NSLog(@"%@",[dicYaoGe objectForKey:@"weight"]);

Running result:

20:47:06. 474 oc07 _ dictionary [6837: 303] 105

Quick traversal:

        for (NSString *key in dicYaoGe) {            NSLog(@"%@ - %@",key ,[dicYaoGe objectForKey:key]);        }

Running result:

20:47:06. 475 oc07 _ dictionary [6837: 303] age-18

20:47:06. 476 oc07 _ dictionary [6837: 303] Sex -?

20:47:06. 476 oc07 _ dictionary [6837: 303] weight-105

20:47:06. 477 oc07 _ dictionary [6837: 303] Name-yao Ge

Common nsmutabledictionary Methods

Nsmutabledictionary * diczijie = [nsmutabledictionary dictionarywithobjectsandkeys: @ "", @ "name", @ "difficult to judge", @ "sex", @ "", @ "Age", @ "200", @ "weight", nil]; for (nsstring * key in diczijie) {nslog (@ "% @-% @", key, [diczijie objectforkey: Key]);}

Running result:

20:57:55. 310 oc07 _ dictionary [6858: 303] age-

20:57:55. 311 oc07 _ dictionary [6858: 303] Hoby -- male

20:57:55. 311 oc07 _ dictionary [6858: 303] weight -- 200

20:57:55. 312 oc07 _ dictionary [6858: 303] Name -- Wang zijie

1. Add a key-value pair.

<span style="white-space:pre"></span>[dicZijie setValue:@"LOL" forKey:@"hoby"];

2. Modify the value corresponding to the key

<Span style = "white-space: pre"> </span> [diczijie setvalue: @ "male" forkey: @ "Hoby"];

3. delete a key-value pair.

<span style="white-space:pre"></span>[dicZijie removeObjectForKey:@"sex"];

4. traverse all key-value pairs through the For Loop

<span style="white-space:pre"></span>for (NSString *key in dicZijie) {                NSLog(@"%@-%@",key , [dicZijie objectForKey:key]);            }

Running result:

21:00:49. 198 oc07 _ dictionary [6872: 303] age-

21:00:49. 199 oc07 _ dictionary [6872: 303] Hoby-male

21:00:49. 199 oc07 _ dictionary [6872: 303] weight-200

21:00:49. 200 oc07 _ dictionary [6872: 303] Name-Wang zijie

For dictionary traversal in an array:

<Span style = "white-space: pre"> </span> nsdictionary * dicdage = [nsdictionary dictionarywithobjectsandkeys: @ "", @ "name", @ "", @ "Hoby", @ "male", @ "sex", nil]; nsmutablearray * Tongji = [nsmutablearray arraywithobjects: diczijie, dicyaoge, dicdage, nil]; for (nsdictionary * DIC in Tongji) {nslog (@ "______________"); For (nsstring * key in DIC) {nslog (@ "% @ -- % @", key, [DIC objectforkey: Key]) ;}}

Running result:

21:00:49. 201 oc07 _ dictionary [6872: 303] ______________

21:00:49. 201 oc07 _ dictionary [6872: 303] age-

21:00:49. 201 oc07 _ dictionary [6872: 303] Hoby -- male

21:00:49. 202 oc07 _ dictionary [6872: 303] weight -- 200

21:00:49. 202 oc07 _ dictionary [6872: 303] Name -- Wang zijie

21:00:49. 203 oc07 _ dictionary [6872: 303] ______________

21:00:49. 203 oc07 _ dictionary [6872: 303] age -- 18

21:00:49. 204 oc07 _ dictionary [6872: 303] sex --?

21:00:49. 204 oc07 _ dictionary [6872: 303] weight -- 105

21:00:49. 205 oc07 _ dictionary [6872: 303] Name -- Yao Ge

21:00:49. 205 oc07 _ dictionary [6872: 303] ______________

21:00:49. 206 oc07 _ dictionary [6872: 303] Name -- Eldest Brother

21:00:49. 206 oc07 _ dictionary [6872: 303] Hoby -- selling medicine

21:00:49. 207 oc07 _ dictionary [6872: 303] Sex-male

OC's Seventh-Day dictionary lesson7