c# - How can I get my graph updating? -

currently working on project takes cpu temperature , put cool graph. takes first value given stops. doesn't keep updating. have tried while loops not seem work. current code:

using system; using system.windows.forms; using system.collections.generic; using system.drawing; using system.drawing.drawing2d; using openhardwaremonitor; using openhardwaremonitor.hardware;  namespace pc_version {     public class circularprogressbar : control      {       #region "properties"     private color _bordercolor;     public color bordercolor     {         { return _bordercolor; }         set         {             _bordercolor = value;             this.invalidate();         }     }      private color _innercolor;     public color innercolor     {         { return _innercolor; }         set         {             _innercolor = value;             this.invalidate();         }     }      private bool _showpercentage;     public bool showpercentage     {         { return _showpercentage; }         set         {             _showpercentage = value;             this.invalidate();         }     }      private int _borderwidth;     public int borderwidth     {         { return _borderwidth; }         set         {             _borderwidth = value;             this.invalidate();         }     }      private float _value;     public float value     {         { return _value; }         set         {   //----------------------------------getting cpu temps--------------------------                                computer thiscomputer;                 thiscomputer = new computer() { cpuenabled = true };                 thiscomputer.open();                 string temp = "";                  list<string> list = new list<string>();                  foreach (var hardwareitem in thiscomputer.hardware)                 {                     if (hardwareitem.hardwaretype == hardwaretype.cpu)                     {                         hardwareitem.update();                         foreach (ihardware subhardware in hardwareitem.subhardware)                             subhardware.update();                           //temps                         foreach (var sensor in hardwareitem.sensors)                         {                             if (sensor.sensortype == sensortype.temperature)                             {                                 temp = sensor.value.tostring();                                  int chunksize = 2;                                 int stringlength = temp.length;                                 (int = 0; < stringlength; += chunksize)                                 {                                     if (i + chunksize > stringlength) chunksize = stringlength - i;                                     list.add(temp.substring(i, chunksize));                                  }                               }                          }                      }                  }  //  ---------------------------------- giving graph value--------------------                 float average = float.parse(list[4]);                   _value = average;                 this.invalidate();              }         }     // -----------------------------drawing graph---------------------------------------------------------------      #endregion      #region "constructor"     public circularprogressbar()     {         setstyle(controlstyles.allpaintinginwmpaint, true);         setstyle(controlstyles.resizeredraw, true);         setstyle(controlstyles.optimizeddoublebuffer, true);         _value = 100;         _bordercolor = color.orange;         _borderwidth = 30;         _showpercentage = true;         _innercolor = color.darkgray;         this.forecolor = color.white;      }     #endregion         #region "painting"     protected override void onpaint(painteventargs e)     {          base.onpaint(e);         e.graphics.smoothingmode = smoothingmode.antialias;          //measure single parts         int diameter = math.min(this.clientsize.width, this.clientsize.height);         int innerdiameter = diameter - borderwidth;         rectangle pierect = new rectangle(convert.toint32(this.clientsize.width / 2 - diameter / 2), convert.toint32(this.clientsize.height / 2 - diameter / 2), diameter, diameter);         rectangle innerrect = new rectangle(convert.toint32(this.clientsize.width / 2 - innerdiameter / 2), convert.toint32(this.clientsize.height / 2 - innerdiameter / 2), innerdiameter, innerdiameter);          //draw outer ring          using (solidbrush b = new solidbrush(bordercolor))         {             e.graphics.fillpie(b, pierect, 0, value / 100 * 360);          }          //draw inner ring         using (solidbrush b = new solidbrush(this._innercolor))         {             e.graphics.fillellipse(b, innerrect);         }          //draw percentage         if (showpercentage)         {             using (stringformat sf = new stringformat())             {                 sf.alignment = stringalignment.center;                 sf.linealignment = stringalignment.center;                 using (solidbrush b = new solidbrush(this.forecolor))                 {                     e.graphics.drawstring(convert.toint32(value).tostring() + "°c", this.font, b, innerrect, sf);                 }             }         }         this.update();     } }     #endregion   } 

this image of result: http://pasteboard.co/payhmnb.png

how can add existing code keep updating value , value on form? thank you

this straight forward. strip out logic setter on value property , put own function, it's bad practice place logic getters , setters beyond getting , setting private member value. this:

timer polltimer = new system.timers.timer(1000); // fires every second  public void initialize() {    // subscribe polltemperature function elapsed event.    polltimer.elapsed += polltemperature;    // enable periodic polling    polltimer.enabled = true; }  private float _value; public float value {     { return _value; }     set     {         if(_value != value)        {           _value = value        }     }  }   public decimal gettemperature()  {     // temperature of cpu sensor here     float yourtemperature = resultsofyourlogic;     return yourtemperature;  }   void polltemperature(object source, elapsedeventargs e)  {     value = gettemperature();     this.invalidate();     this.update();  }  

this sets timer polls temperatures every second , updates value property. invalidates control , updates redraw it.