Javascript – Align text right using jsPDF

javascriptjspdf

I'm using jsPDF to create a PDF on the client side and I see there are properties to change the color, size, and font of the text, but I need to align the text to the right. So it's all aligned to a right coordinate. Kind of like text-align: right; in CSS. How would I go about doing this?

Thanks

Best Solution

I have written an extension to jsPDF a while back that allows text aligning (and by default aligns top-left, instead of the random stuff jsPDF' .text function does).

The code is written in TypeScript (to add some type annotations), which should give you a pretty clear idea what parameters there are.

Update: These snippets have been corrected to work in the latest version as of 2019/07/17, thanks to Kaddath (see their comment/this post's edit history for details).

var splitRegex = /\r\n|\r|\n/g;
jsPDF.API.textEx = function (text: any, x: number, y: number, hAlign?: string, vAlign?: string) {
    var fontSize = this.internal.getFontSize()
        / this.internal.scaleFactor;

    // As defined in jsPDF source code
    var lineHeightProportion = 1.15;

    var splittedText: string[];
    var lineCount: number = 1;
    if (vAlign === 'middle' || vAlign === 'bottom'
        || hAlign === 'center' || hAlign === 'right') {

        splittedText = typeof text === 'string'
        ? text.split(splitRegex)
        : text;

        lineCount = splittedText.length || 1;
    }

    // Align the top
    y += fontSize * (2 - lineHeightProportion);

    if (vAlign === 'middle') y -= (lineCount / 2) * fontSize;
    else if (vAlign === 'bottom') y -= lineCount * fontSize;


    if (hAlign === 'center'
        || hAlign === 'right') {

        var alignSize = fontSize;
        if (hAlign === 'center') alignSize *= 0.5;

        if (lineCount > 1) {
            for (var iLine = 0; iLine < splittedText.length; iLine++) {
                this.text(splittedText[iLine],
                    x - this.getStringUnitWidth(splittedText[iLine]) * alignSize,
                    y);
                y += fontSize * lineHeightProportion;
            }
            return this;
        }
        x -= this.getStringUnitWidth(text) * alignSize;
    }

    this.text(text, x, y);
    return this;
};

Plain javascript:

var splitRegex = /\r\n|\r|\n/g;
jsPDF.API.textEx = function (text, x, y, hAlign, vAlign) {
    var fontSize = this.internal.getFontSize() / this.internal.scaleFactor;

    // As defined in jsPDF source code
    var lineHeightProportion = 1.15;

    var splittedText = null;
    var lineCount = 1;
    if (vAlign === 'middle' || vAlign === 'bottom' || hAlign === 'center' || hAlign === 'right') {
        splittedText = typeof text === 'string' ? text.split(splitRegex) : text;

        lineCount = splittedText.length || 1;
    }

    // Align the top
    y += fontSize * (2 - lineHeightProportion);

    if (vAlign === 'middle')
        y -= (lineCount / 2) * fontSize;
    else if (vAlign === 'bottom')
        y -= lineCount * fontSize;

    if (hAlign === 'center' || hAlign === 'right') {
        var alignSize = fontSize;
        if (hAlign === 'center')
            alignSize *= 0.5;

        if (lineCount > 1) {
            for (var iLine = 0; iLine < splittedText.length; iLine++) {
                this.text(splittedText[iLine], x - this.getStringUnitWidth(splittedText[iLine]) * alignSize, y);
                y += fontSize * lineHeightProportion;
            }
            return this;
        }
        x -= this.getStringUnitWidth(text) * alignSize;
    }

    this.text(text, x, y);
    return this;
};

Using it is as simple as:

pdf.textEx('Example text', xPosition, yPosition, 'right', 'middle');

Prints a text of which the middle right is at (xPosition, yPosition).