xpanel.save(ms, system.drawing.imaging.imageformat.png); should save in memory stream, ms, each line drawn showing 9 ellipses. below there no output png objgraphicpanel.fillrectangle screen. missing "f" in pointf x1, y1, x2 , y2 single floats.
protected void page_load(object sender, eventargs e) { ... using (bitmap xpanel = new bitmap(500, 500)) { using (graphics objgraphicpanel = graphics.fromimage(xpanel)) { //background white solidbrush whitebrush = new solidbrush(color.white); objgraphicpanel.fillrectangle(whitebrush, 0, 0, 200, 200); pen colorpen = new pen(color.black, 2); memorystream ms = new memorystream(); (k = 1; k <= 9; k++) { (int nn = 2; nn <= n; nn++) { float x1 = convert.tosingle(xyecl[k, nn - 1]); float y1 = convert.tosingle(zyecl[k, nn - 1]); float x2 = convert.tosingle(xyecl[k, nn]); float y2 = convert.tosingle(zyecl[k, nn]); pointf[] ptf = { new pointf(x1, y1), new pointf(x2, y2) }; objgraphicpanel.drawlines(colorpen, ptf); xpanel.save(ms, system.drawing.imaging.imageformat.png); } } string imgbase64 = convert.tobase64string(ms.toarray()); myimage.src = "data:image/png;base64," + imgbase64; objgraphicpanel.dispose(); } xpanel.dispose(); } <img id="myimage" runat="server" />
