CODEWITHSUNDEEP
c#arrays
Kajiyama
Kajiyama

Reputation: 3442

Set array values for specific range in C#

I was looking for a way, how to set specific values for specific range in an array.

Something like this

Pseudocode:

var s = new uint[64];
s[ 0..15] := { 2, 4, 6, 3,  1, 7, 8, 9,  7, 11, 37, 32,  19, 16, 178, 2200 }
s[16..31] := ...

I was trying to find something like this in C#, but with no luck. I am trying to come with something like this:

public void SetArrayValues(int startIndex, uint[] values) 
{
    var length = values.Length;
    this.array[startIndex, startIndex + length] = values;
}

The only thing I was able to find was System.Array.SetValue but this does not meet my requirements.

Upvotes: 7

Views: 15108

Answers (5)

Matthew Watson
Matthew Watson

Reputation: 109567

You could write an extension method to make this simpler:

public static class ArrayExt
{
    public static T[] Set<T>(this T[] self, int index, params T[] values)
    {
        Array.Copy(values, 0, self, index, values.Length);
        return self;
    }
}

Using it would look like this:

var s = new uint[64];
s.Set<uint>(0, 2, 4, 6, 3, 1, 7, 8, 9, 7, 11, 37, 32, 19, 16, 178, 2200);

Because Set() returns the array, you can also chain calls like this:

s.Set<uint>( 0, 2, 4, 6, 3, 1, 7, 8, 9, 7, 11, 37, 32, 19, 16, 178, 2200)
 .Set<uint>(16, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,  15,   16);

Note: The requirement to explicitly put the type into the call comes from the fact that we're using ints in the list of values.

You should really use uint since the destination is uint, then there is no need to specify the type:

var s = new uint[64];
s.Set(0, 2u, 4u, 6u, 3u, 1u, 7u, 8u, 9u, 7u, 11u, 37u, 32u, 19u, 16u, 178u, 2200u);

And of course it works with all types, e.g. string:

var x = new string[64];
x.Set(10, "A", "B", "C");

Upvotes: 3

Julius Depulla
Julius Depulla

Reputation: 1633

You can do it in a couple ways. Because I do not know you requirements and your code, I know you would need to modify this to suit you. But C# arrays are unlike C++ arrays, so the index always start from zero.

UInt64[] list = {2, 4, 6, 3, 1, 7, 8, 9, 7, 11, 37, 32, 19, 16, 178, 2200,..}; 
//Length of the list must be 31. That is contain 31 numbers.

UInt64[] s= new UInt64[31];

// You can have all the collection  

for (int i = 0; i < list.Length; i++)
{
    s[i] = list[i];
}    

// Or you can modify as below

for (int i = 0; i < 15; i++)
{
    s[i] = list[i];
}

for (int i = 16; i < 31; i++)
{
    s[i] = list[i];
}

Upvotes: 0

Konstantin Chernov
Konstantin Chernov

Reputation: 1936

First you define your Arrays 

    s1 := { ... }
    s2 := { ... }
    s3 := { ... }
    ...
    sn := { ... }

Then just concat them in a linq method chain

var result = s1.Concat(s2).Concat(s3)....Concat(sn);

You can do it in whatever order you like and get the exact result. It's easy to change the resulting sequence just by altering the chain slightly.

Upvotes: 0

Saeb Amini
Saeb Amini

Reputation: 24390

I think the closest you can do is via Array.Copy:

var s = new uint[64];
uint[] values = { 2, 4, 6, 3, 1, 7, 8, 9, 7, 11, 37, 32, 19, 16, 178, 2200 };

int sourceIndex = 0;
int destinationIndex = 0;
Array.Copy(values, sourceIndex , s, destinationIndex , values.Length);

Upvotes: 18

Peter Szekeli
Peter Szekeli

Reputation: 2800

Not an exact match to the method you described, but you could create a List<int> and use the AddRange() method. Once you've added all the values, you can use to ToArray() method to turn it to an array.

var numbers = new List<int>();
numbers.AddRange(new List<int>{ 2, 4, 6, 3,  1, 7, 8, 9,  7, 11, 37, 32,  19, 16, 178, 2200 });
//numbers.AddRange(new List<int> { ... });

var asArray = numbers.ToArray();

Upvotes: 0

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