Get all object from NSMutableArray into string using for loop

Question

In my code I have an NSMutableArray. I want to get all values from that array into String and I want to send to the server. I used a for loop but it doesn't work. I don't know what I did wrong. Please help to fix the issue.

Here the code I tried.

var newString1 = String()
for i in (0..<self.idMutableArray.count)
{
    newString1 = (idMutableArray.object(at: i) as! NSString) as String
    print("newString1 is ",newString1)
}
print("newString1 is ",newString1)

The mutable array Format is:

idMutableArray is  (
        31,
        30,
        29,
        42,
        50
    )

When I am tried I get this format:

newString1 is  29
newString1 is  30
newString1 is  31
newString1 is  42
newString1 is  50

But I want to send this format to the server.

newString1 = 31,30,29,42,50

I don't know how to change that array to string format. Please help me.

Why are you using NSMutableArray instead of a Swift array? Why NSString instead of String? — rmaddy
– rmaddy, Commented May 15, 2017 at 15:05
Why dont you iterate with the object instead? I mean: for i in idMutableArray { newString = i as! NSString } — Aitor Pagán
– Aitor Pagán, Commented May 15, 2017 at 15:09
I am new for Swift and don't know for how to use swift array? — B.Saravana Kumar
– B.Saravana Kumar, Commented May 15, 2017 at 15:09
You don't need a loop for this, just use componentsJoined (or joined for a Swift array). — John Montgomery
– John Montgomery, Commented May 15, 2017 at 15:12
If you don't know how to use Swift arrays then you need to read the Collection Types section of the "The Swift Programming Language" book (along with the rest of the book). — rmaddy
– rmaddy, Commented May 15, 2017 at 15:13

Ozgur Vatansever · Accepted Answer · 2017-05-15 15:22:54Z

2

Avoid using NS collection types in favor of standart Swift counterparts Array and Dictionary. You can start reading this if you want to find out more about them.

let idMutableArray = ["31", "30", "29", "42", "50"]
let newString1 = idMutableArray.joined(separator: ",")

However, if you have to use NSMutableArray, here is what you can do:

let idMutableArray = NSMutableArray(objects: "31", "30", "29", "42", "50")
let newString1 = idMutableArray.idMutableArray.componentsJoined(by: ",")

print(newString1) # will print "31,30,29,42,50"

edited May 15, 2017 at 15:22

answered May 15, 2017 at 15:13

Ozgur Vatansever

52.5k17 gold badges89 silver badges122 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

rmaddy Over a year ago

While this is the most direct answer, the OP should not be using NSMutableArray.

B.Saravana Kumar Over a year ago

let newString1 = idMutableArray.joined(separator: ",") it is got some validation problem in next functionality.

Ozgur Vatansever Over a year ago

what do you mean by validation problem?

Max Pevsner · Accepted Answer · 2017-05-15 15:10:15Z

1

If you want all the values in one string, you should add them to that string and not to override it in each iteration.

var newString1 = ""
for i in (0..<idMutableArray.count)
{
    newString1 += String(describing: idMutableArray[i])
    if i < idMutableArray.count - 1 {
        newString1 += ","
    }
    print("newString1 is ",newString1)
}
print("newString1 is ",newString1)

answered May 15, 2017 at 15:10

Max Pevsner

4,0842 gold badges20 silver badges32 bronze badges

Comments

vadian · Accepted Answer · 2017-05-15 15:15:20Z

1

First of all you don't need NSMutableArray. Use Swift Array

let idMutableArray = ["31", "30", "29", "42", "50"]

Second of all you don't need a repeat loop, just join the strings.

let newString1 = idMutableArray.joined(separator: ",")
print("newString1 is ",newString1)

edited May 15, 2017 at 15:15

answered May 15, 2017 at 15:13

vadian

286k32 gold badges378 silver badges379 bronze badges

4 Comments

rmaddy Over a year ago

Given the code in the question, it appears to be an array of NSString, not an array of numbers.

vadian Over a year ago

Thanks, I was confused about the array dump (missing double quotes)

B.Saravana Kumar Over a year ago

let newString1 = idMutableArray.joined(separator: ",") it is got some validation problem in next functionality.

vadian Over a year ago

Change all Foundation types to Swift types. It's worth it.

Daniel Storm · Accepted Answer · 2017-05-15 15:23:39Z

1

You're assigning a new value to your string each time your for loop runs:

newString1 = (idMutableArray.object(at: i) as! NSString) as String

You can use joined(separator:) to get the desired output:

let array = ["1", "2", "3", "4", "5"]
let string = array.joined(separator: ",")
print("\(string)") // Prints "1,2,3,4,5"

edited May 15, 2017 at 15:23

answered May 15, 2017 at 15:15

Daniel Storm

18.9k10 gold badges89 silver badges156 bronze badges

1 Comment

rmaddy Over a year ago

This is wrong. It prints 1,2,3,4,5,. Note the trailing comma.

Collectives™ on Stack Overflow

Get all object from NSMutableArray into string using for loop

4 Answers 4

3 Comments

Comments

4 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

3 Comments

Comments

4 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related