我需要在使用jsPDF(https://mrrio.github.io/jsPDF/doc/symbols/jsPDF.html)创建的PDF中绘制一条虚线
创建一个简单的行:
doc.line(20, 25, 60, 25);
如何创建虚线或虚线?
我有同样的问题,并且这样做:
/**
* Draws a dotted line on a jsPDF doc between two points.
* Note that the segment length is adjusted a little so
* that we end the line with a drawn segment and don't
* overflow.
*/
function dottedLine(doc, xFrom, yFrom, xTo, yTo, segmentLength)
{
// Calculate line length (c)
var a = Math.abs(xTo - xFrom);
var b = Math.abs(yTo - yFrom);
var c = Math.sqrt(Math.pow(a,2) + Math.pow(b,2));
// Make sure we have an odd number of line segments (drawn or blank)
// to fit it nicely
var fractions = c / segmentLength;
var adjustedSegmentLength = (Math.floor(fractions) % 2 === 0) ? (c / Math.ceil(fractions)) : (c / Math.floor(fractions));
// Calculate x, y deltas per segment
var deltaX = adjustedSegmentLength * (a / c);
var deltaY = adjustedSegmentLength * (b / c);
var curX = xFrom, curY = yFrom;
while (curX <= xTo && curY <= yTo)
{
doc.line(curX, curY, curX + deltaX, curY + deltaY);
curX += 2*deltaX;
curY += 2*deltaY;
}
}
更高版本的jsPDF
具有内置功能:
setLineDash
[Docs]
例如,下面绘制一条虚线,画出10mm的线条,然后沿着从左到右的方向重复10mm的空间。我假设您正在绘制一个具有所有默认设置(即A4,mm单位等)的页面:
doc.setLineDash([10, 10], 0);
doc.line(20, 25, 60, 25);
下面将绘制7毫米的线,3毫米的空间,1毫米的线,3毫米的空间然后重复,然而,它将启动10毫米的图案,因此要绘制的仪表板的第一部分是1毫米部分:
doc.setLineDash([7, 3, 1, 3], 10);
doc.line(20, 25, 60, 25);