如何在NSArray中獲取索引？

Question

NSMutableArray*array = [[NSMutableArray alloc]init];

NSArray*Somearray = [NSArray arrayWithObjects:1st Object,2ndObject,3rd Object,4th object,5th Object,nil];

在上面的數組中，第一對象，第二對象，第三對象，第四對象，第五對象在每個索引中具有val，內容，結論。

for(int i=0;i<[Somearray count];i++)
{

______________

Here the code is there to give each index ,that is having val,content,conclusion ..

After that  val,content,conclusion in each index will be add to Dict..
____________


NSDictionary *Dict = [NSDictionary dictionaryWithObjectsAndKeys:val,@"val",content,@"content",conclusion,@"conclusion",nil];

//Each time adding dictionary into array;

[array addObject:Dict];

}

上面的Dictionary是for循環，keyvalue對將被添加5次（Somearray Count）。現在有數組

array = [{val="1.1 this is first one",content="This is the content of 0th index",conclusion="this is  the conclusion of 0th index"},{val="1.2 this is first one",content="This is the content of 1st index",conclusion="this is  the conclusion of 1st index"},____,____,______,{val="1.5 this is first one",content="This is the content of 4th index",conclusion="this is  the conclusion of 4th index"},nil];

現在我有NSString*string = @"1.5";

現在我需要val中有1.5的索引。如何將str發送到數組以查找索引。

任何人都可以共享代碼。

提前致謝。

Answer 1

使用方法indexOfObject

int inx= [array indexOfObject:@"1.5"];

用於查找索引特定鍵值。

int inx;
for (int i=0; i<[array count]; i++) {
    if ([[[array objectAtIndex:i] allKeys] containsObject:@"val"]) {
        inx=i;
         break; 
    }
}

Answer 2

您正在尋找的方法是-[NSArray indexOfObjectPassingTest:] 。 你會像這樣使用它：

NSUInteger i = [array indexOfObjectPassingTest:^(id obj, NSUInteger idx, BOOL *stop) {
        return [[id objectForKey:@"val"] rangeOfString:@"1.5"].location != NSNotFound;
    }];

如果你只想檢查val以“1.5”開頭，你將使用hasPrefix:而不是。

Answer 3

嘗試這個 -

NSArray *valArray = [array valueForKey:@"val"];
int index = [valArray indexOfObject:@"1.5"]; 

Mandeep給出的附加答案，向您展示鍵值編碼的魔力;）

Answer 4

 NSUInteger idx = UINT_MAX;
    NSCharacterSet* spaceSet = [NSCharacterSet whitespaceCharacterSet];
    for(int i=0,i_l=[Yourarray count];i<i_l;i++) {
        NSString* s_prime = [[Yourarray objectAtIndex:i] valueForKey:@"val"];
        if ([s_prime length] < 4) {
            continue;
        }
        NSString *subString = [[s_prime substringToIndex:4] stringByTrimmingCharactersInSet:spaceSet];
       // NSLog(@"index %@",s);
        if ([subString isEqualToString:secretNumber]){
            idx = i;
            break;
        }
    }
    if (idx != UINT_MAX) {
      //  NSLog(@"Found at index: %d",idx);
    } else {
     //   NSLog(@"Not found");
    }