How to take a long curve, c #.-CodePudding

How many data, in the winfrom words long graph, the need to have a scroll bar, can drag back and forth, for advice,

CodePudding user response:

To find a third party controls

CodePudding user response:

Can you give a specific direction, thank you.

CodePudding user response:

You use the panel first stratification, do a canvas

CodePudding user response:

refer to the original poster azhou88 response:

a lot of data, how words in winfrom long graph, the following needs to have a scroll bar, you can drag back and forth, consult,

Mschart have drag, also have a scroll bar

CodePudding user response:

According to the position of the scroll bar to determine shows that a data,
Changes such as the following example code (micro), illustrates the 300 million data graphical,

Code references since l: [quote]
https://bbs.csdn.net/topics/390614100
13 floor
C # the big data processing [question points: 100 minutes, "post man porenasckx

 
Using System. IO; 
Using System. IO. MemoryMappedFiles; 

Public partial class Form1: Form 
{
Public _click () 
{
//InitializeComponent (); 
The string filename="example. Dat"; 
if (! File. The Exists (filename)) 
{
MessageBox. Show (" run for the first time... Create a 300 MB data file: "+ filename); 
GenerateData (filename); 
} 
This. We=we. CreateFromFile (filename); 
Enclosing scrollbar=new HScrollBar () 
{
Height=32, 
The Dock=DockStyle. Bottom, 
Maximum=(int) (new to the FileInfo (filename). Length/4), 
}; 
This. The scrollbar. ValueChanged +=(sender, e)=& gt; This Invalidate (invalidateChildren: false); 
This. Controls. The Add (scrollbar); 
Enclosing DoubleBuffered=true; 
This. Size=new Size (800, 600); 
} 
ScrollBar ScrollBar. 
We we; 

Protected override void OnPaint (PaintEventArgs e) 
{
Base. The OnPaint (e); 
Int from=100; 
Int start=Math. Min (this) scrollbar) Value, enclosing scrollbar. Maximum - from); 
Um participant raphics. DrawCurve (Pens. Black, GetPoints (start from)); 
Um participant raphics. DrawString (start. ToString (n0), enclosing the Font, Brushes, DarkBlue, new Point (200, 15)); 
} 

Private PointF [] GetPoints (int start, int count) 
{
List Points=new List (count); 
Using (var viewStream=we CreateViewStream (start * sizeof (float), the count * sizeof (float))) 
Using (var reader=new BinaryReader (viewStream)) 
{
for (int i=0; I & lt; The count. I++) 
{
Float x=I * this. ClientRectangle. Width/100; 
Float y=reader. ReadSingle (). * this ClientRectangle. Height; 
Points. The Add (new PointF (x, y)); 
} 
} 
Return points. ToArray (); 
} 

Private void GenerateData (string outputFile, int count=75 * 1024 * 1024) 
{
The Random Random=new Random (123); 
Using (BinaryWriter writer=new BinaryWriter (new FileStream (outputFile, FileMode. Create))) 
{
Float last=0.5 f; 
for (int i=0; I & lt; The count. I++) 
{
Last=last + (float) (random NextDouble () 0.5)/20; 
Last=Math. Max (0, Math. Min (last, 1)); 
Writer. Write (last); 
} 
} 
} 
}

CodePudding user response:

Thank you, you said I'll be careful, look at the method to use, thank you, turn head junction points, points, knot predestination,

CodePudding user response:

CSDN good master much more,