c# - “IImageProcessingContext”不包含“ApplyScalingWaterMark”ImageSharp 的定义

Question

我正在运行最新版本，并且收到上述错误。

严重性代码描述项目文件行抑制状态错误 CS1061“IImageProcessingContext”不包含“ApplyScalingWaterMark”的定义，并且找不到接受“IImageProcessingContext”类型的第一个参数的可访问扩展方法“ApplyScalingWaterMark”（您是否缺少 using 指令或程序集参考？）GitHubFuncs C:\Sibeesh\Github\GitHubFuncs\GetLatestPosts.cs 39 活动

当我运行下面的代码时。

using(var img = Image.Load("canvas.jpg")) {
    Font font = SystemFonts.CreateFont("Arial", 10);
    using
    var img2 = img.Clone(ctx => ctx.ApplyScalingWaterMark(font, feedItem.Summary.Text, Color.HotPink, 5, true));
    img2.Save("images/wrapped.png");
}

已经添加了 using 语句。

using SixLabors.Fonts;
using SixLabors.ImageSharp.Drawing;
using SixLabors.ImageSharp;
using SixLabors.ImageSharp.Processing;

我在这里想念什么？这是最新版本的问题吗？

标签： c#.netasp.net-core.net-coreimagesharp

Answer 1

最后，我让它工作了。我只需要添加一些扩展方法。

using SixLabors.Fonts;
using SixLabors.ImageSharp;
using SixLabors.ImageSharp.Drawing.Processing;
using SixLabors.ImageSharp.Processing;
using System;

namespace GitHubFuncs.ExtensionMethods {
    public static class ImageSharpExtensions {
        public static IImageProcessingContext ApplyScalingWaterMark(this IImageProcessingContext processingContext,
            Font font,
            string text,
            Color color,
            float padding,
            bool wordwrap) {
            if (wordwrap) {
                return processingContext.ApplyScalingWaterMarkWordWrap(font, text, color, padding);
            } else {
                return processingContext.ApplyScalingWaterMarkSimple(font, text, color, padding);
            }
        }
        private static IImageProcessingContext ApplyScalingWaterMarkSimple(this IImageProcessingContext processingContext,
            Font font,
            string text,
            Color color,
            float padding) {
            Size imgSize = processingContext.GetCurrentSize();

            float targetWidth = imgSize.Width - (padding * 2);
            float targetHeight = imgSize.Height - (padding * 2);

            // measure the text size
            FontRectangle size = TextMeasurer.Measure(text, new RendererOptions(font));

            //find out how much we need to scale the text to fill the space (up or down)
            float scalingFactor = Math.Min(imgSize.Width / size.Width, imgSize.Height / size.Height);

            //create a new font
            Font scaledFont = new Font(font, scalingFactor * font.Size);

            var center = new PointF(imgSize.Width / 2, imgSize.Height / 2);
            var textGraphicOptions = new TextGraphicsOptions() {
                TextOptions = {
                    HorizontalAlignment = HorizontalAlignment.Center,
                    VerticalAlignment = VerticalAlignment.Center
                }
            };
            return processingContext.DrawText(textGraphicOptions, text, scaledFont, color, center);
        }

        private static IImageProcessingContext ApplyScalingWaterMarkWordWrap(this IImageProcessingContext processingContext,
            Font font,
            string text,
            Color color,
            float padding) {
            Size imgSize = processingContext.GetCurrentSize();
            float targetWidth = imgSize.Width - (padding * 2);
            float targetHeight = imgSize.Height - (padding * 2);

            float targetMinHeight = imgSize.Height - (padding * 3); // must be with in a margin width of the target height

            // now we are working i 2 dimensions at once and can't just scale because it will cause the text to
            // reflow we need to just try multiple times

            var scaledFont = font;
            FontRectangle s = new FontRectangle(0, 0, float.MaxValue, float.MaxValue);

            float scaleFactor = (scaledFont.Size / 2); // every time we change direction we half this size
            int trapCount = (int) scaledFont.Size * 2;
            if (trapCount < 10) {
                trapCount = 10;
            }

            bool isTooSmall = false;

            while ((s.Height > targetHeight || s.Height < targetMinHeight) && trapCount > 0) {
                if (s.Height > targetHeight) {
                    if (isTooSmall) {
                        scaleFactor = scaleFactor / 2;
                    }

                    scaledFont = new Font(scaledFont, scaledFont.Size - scaleFactor);
                    isTooSmall = false;
                }

                if (s.Height < targetMinHeight) {
                    if (!isTooSmall) {
                        scaleFactor = scaleFactor / 2;
                    }
                    scaledFont = new Font(scaledFont, scaledFont.Size + scaleFactor);
                    isTooSmall = true;
                }
                trapCount--;

                s = TextMeasurer.Measure(text, new RendererOptions(scaledFont) {
                    WrappingWidth = targetWidth
                });
            }

            var center = new PointF(padding, imgSize.Height / 2);
            var textGraphicOptions = new TextGraphicsOptions() {
                TextOptions = {
                    HorizontalAlignment = HorizontalAlignment.Left,
                    VerticalAlignment = VerticalAlignment.Center,
                    WrapTextWidth = targetWidth
                }
            };
            return processingContext.DrawText(textGraphicOptions, text, scaledFont, color, center);
        }
    }
}

最后，我可以像前面那样使用这种方法。

private static string WriteOnImage(SyndicationItem feedItem) {
    using var img = Image.Load("images/canvas.jpg");
    var font = SystemFonts.CreateFont("Arial", 20);
    using var img2 = img.Clone(ctx => ctx.ApplyScalingWaterMark(font, feedItem.Summary.Text, Color.White, 5, true));
    return img2.ToBase64String(PngFormat.Instance);
}