asp.net - How to create a global variable in C#? -

i need use global variable in .net project. however, cannot handle between 2 methods..

my code:

string str; protected void page_load(object sender, eventargs e) {     if (!page.ispostback)     {         str = "i string";         showstring();     } }  void showstring() {     asplabel.text = str; //error } 

question update:

i not consider use showstring(str) because variable used many methods.. example, have click event need use it.

protected void btn_click(object sender, eventargs e) {     exporttoexcel(str); } 

therefore, need create in global!

the answer don't global variables (you can't).

closest global having in class static , has static member - think wrong approach of cases. static classes/members make code more coupled , reduces testability pick when decide so.

do instead: (pass parameter)

protected void page_load(object sender, eventargs e) {   if (!page.ispostback)   {     string str = "i string";     showstring(str);   } }  void showstring(string str) {   asplabel.text = str; } 

or:

public class someclass {     private string str;      protected void page_load(object sender, eventargs e)     {       if (!page.ispostback)       {         str = "i string";         showstring();       }     }      protected void btn_click(object sender, eventargs e)     {        exporttoexcel(str);     }      void showstring()     {       asplabel.text = str;     } } 

here can change str property or different access modifier wish, general idea.

if have public instead of private able access different classes hold instance class. this:

public class someclass {     public string str { get; private set; }      protected void page_load(object sender, eventargs e)     {       if (!page.ispostback)       {         str = "i string";         showstring();       }     }      protected void btn_click(object sender, eventargs e)     {        exporttoexcel(str);     }      void showstring()     {       asplabel.text = str;     } }  public class someotherclass {     public someotherclass()     {         someclass someclass = new someclass();         var otherstr = someclass.str;     } }