如何在不指定每个段落在SharpPDF中的确切坐标的情况下创建段落？

Question

我是否可以使用SharpPDF添加段落，而不必指定确切的坐标？我不能把一个段落放在另一个段落下面吗？

如果你用过图书馆，请告诉我。

Answer 1

在不指定坐标的情况下，不可能一个接一个地添加段落，但是我确实写了这个示例，它将在页面中向下移动段落，并在必要时创建一个新页面。在这种情况下，你可以写出文本，段落，绘图，并且总是知道“光标”的位置。

const int WIDTH = 500;
const int HEIGHT = 792;

pdfDocument myDoc;
pdfPage currentPage;

private void button1_Click(object sender, EventArgs e)
{
    int height = 0;

    myDoc = new pdfDocument("TUTORIAL", "ME");
    currentPage = myDoc.addPage(HEIGHT, WIDTH);

    string paragraph1 = "All the goats live in the land of the trees and the bushes, " 
        + " when a person lives in the land of the trees and the bushes they wonder about the sanity" 
        + " of it all. Whatever.";

    string paragraph2 =  "Redwood National and State Parks is located in northernmost coastal "
        + "California — about 325 miles north of San Francisco, Calif. Roughly 50 miles long, the parklands"
        + "stretch from near the Oregon border in the north to the Redwood Creek watershed southeast of"
        + "Orick, Calif. Five information centers are located along this north-south corrdior. Park "
        + "Headquarters is located in Crescent City, Calif. (95531) at 1111 Second Street.";

    int iYpos = HEIGHT;

    for (int ix = 0; ix < 10; ix++)
    {
        height = GetStringHeight(paragraph1, new Font("Helvetica", 12), WIDTH);
        iYpos = CheckHeight(height, iYpos);
        currentPage.addParagraph(paragraph1, 0, iYpos, sharpPDF.Enumerators.predefinedFont.csHelvetica, 12, WIDTH);
        iYpos -= height;

        height = GetStringHeight(paragraph2, new Font("Helvetica", 12), WIDTH);
        iYpos = CheckHeight(height, iYpos);
        currentPage.addParagraph(paragraph2, 0, iYpos, sharpPDF.Enumerators.predefinedFont.csHelvetica, 12, WIDTH);
        iYpos -= height;
    }

    string tmp = Path.GetFileNameWithoutExtension(Path.GetTempFileName()) + ".pdf";
    myDoc.createPDF(tmp);
}

private int GetStringHeight(string text, Font font, int width)
{
    Bitmap b = new Bitmap(WIDTH, HEIGHT);
    Graphics g = Graphics.FromImage((Image)b);
    SizeF size = g.MeasureString(text, font, (int)Math.Ceiling((float)width / 72F * g.DpiX));
    return (int)Math.Ceiling(size.Height)
}

private int CheckHeight(int height, int iYpos)
{
    if (height > iYpos)
    {
        currentPage = myDoc.addPage(HEIGHT, WIDTH);
        iYpos = HEIGHT;
    }
    return iYpos;
}

在此API中，Y是向后的，因此792是顶部，0是底部。我使用Graphics对象来测量字符串的高度，因为Graphics是以像素为单位的，而Pdf是以点为单位的。然后我从剩余的Y值中减去高度。

在这个例子中，我一遍又一遍地添加paragraph1和paragraph2，同时更新我的Y位置。当我到达页面底部时，我会创建一个新页面并重置我的Y位置。

这个项目已经很多年没有看到任何更新了，但源代码是可用的，使用类似于我所做的事情，你可以制作自己的函数，允许你连续添加段落，它将跟踪光标位置，它认为下一步应该去哪里。