$ cat c-sharp-veri-tipleri-degisken-tanimlama.md

C# Veri Tipleri – Değişken Tanımlama

bu yazı 2008–2013 blog arşivinden, olduğu gibi bırakıldı. bağlantılar ölmüş olabilir

Değişkenler bir programlama dilinde temel verileri saklamak ve bu verileri sonradan kullanmak için kullanılan bellek bölgeleridir.

C#’ta değişken şu şekildeki tanımlanır:

VeriTipi DegiskenAdi ;

Tamsayı veri tipleri; sbyte, byte, short, ushort, int, uint, long, ulong.

Virgüllü Sayı Veri Tipleri; float, double, decimal.

Tek Karakter Veri Tipi; char.

Karakter dizisi Veri Tipi; string.

True/False Veri Tipi; bool.

Tarihsel Veri Tipi; DateTime.

<td valign="bottom" width="118">
  <span style="color: #ff0000;"><strong>CTS Karşılığı</strong></span>
</td>

<td valign="bottom" width="168">
  <span style="color: #ff0000;"><strong>Açıklama</strong></span>
</td>

<td valign="bottom" width="272">
  <span style="color: #ff0000;"><strong>Max ve Min aralık yada değeri</strong></span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Byte</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">8 bit işaretli tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">-128 : 127</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Int16</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">16 bit işaretli tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">-32.768 : 32.767</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Int32</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">32 bit işaretli tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">-2.147.483.648 : 2.147.483.647</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Int64</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">64 bit işaretli tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">-9.223.372.036.854.775.808 : 9.223.372.036.854.775.807</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Byte</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">8 bit işaretsiz tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">0 : 255</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.UInt16</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">16 bit işaretsiz tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">0 : 65.535</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.UInt32</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">32 bit işaretsiz tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">0 : 4.294.967.295</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.UInt64</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">64 bit işaretsiz tamsayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">0 : 18.446.744.073.709.551.615</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Single</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">32 bit tek kayan sayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">+yada &#8211; 1,5*10<sup>-45</sup> : + ya da &#8211; 3,4*10<sup>38 (virgülün sağında ve solunda 7 basamak)</sup></span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">Sytem.Double</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">64 bit çift kayan sayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">+yada &#8211; 5*10<sup>-324</sup> : + ya da &#8211; 1,7*10<sup>308 (virgülün sağında ve solunda 15-16 basamak)</sup></span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Decimal</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">128 bit ondalıklı sayı</span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">+yada &#8211; 1,0*10<sup>-28</sup> : + ya da &#8211; 7,9*10<sup>28 (virgülün sağında ve solunda 28-29 basamak) </sup></span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Boolean</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;"><br /> </span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">true ya da false</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.Char</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">Tek Karakter<br /> </span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">16 Unicode karakterleri</span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.String</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">Karakter dizileri<br /> </span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">16 Unicode karakter dizileri<br /> </span>
</td>
<td valign="bottom" width="118">
  <span style="color: #0000ff;">System.DateTime</span>
</td>

<td valign="bottom" width="168">
  <span style="color: #0000ff;">Tarih<br /> </span>
</td>

<td valign="bottom" width="272">
  <span style="color: #0000ff;">gün/ay/yıl saat &#8211; 23.02.2010 12:00:00 </span>
</td>
C# Adı
sbyte
short
int
long
byte
ushort
uint
ulong
float
double
decimal
bool
char
string
DateTime
byte sayi1 = 0;  //0 ve 255 arası
sbyte sayi2 = -120; //-128 ve 127 arası
//hafızada 1byte yer kaplar

short sayi3 = 15056; //-32768 ve 32767 arası
ushort sayi4 = 65000; //0 ve 65535 arası
//hafızada 2 byte yer kaplar

int sayi5 = 148795413; //-2.147.483.648 ve +2.147.483.647 arası
uint sayi6 = 76745621; // 0 ve 4.294.967.295 arası
//hafızada 4 byte yer kaplar

long sayi7 = -7103456094932;
//-9.223.372.036.854.775.808 ile 9.223.372.036.854.775.807
ulong sayi8 = 1134576849039032; //0 ile 18.446.744.073.709.551.615
//hafızada 8 byte yer kaplar

float sayi9 = 11.29f; //4 byte //-3.402823E38 ve +3.402823E38
double sayi10 = 45.23d; // 8 byte //-1.79769313486232E308 ve +1.79769313486232E308
decimal sayi11 = 123.456M; //16 byte //-7.9E1028 ve +7.9E1028

DateTime Tarih = DateTime.Now; //8 byte // 1/1/0001 12:00:00 ve 31/12/9999 23:59:59
//DateTime.Now - şu anın tarihini atar

string AdSoyad = "Emrah Yumuk" ; // ~ (2 byte x harf adedi) yer kaplar

bool Evet = true; //4 byte //True veya False
bool Hayır = false;

NOT: Eğer tanımladığımız değişkenin en başına “const” yazarsak değişkeni sabitlemiş oluruz. Yazdığımız programda bir daha bu değişkeni değiştiremeyiz.

const int Sayi = 25;

← archive