找到换行

Question

假设我在一行中有一些随机的文本块.像这样

Lorem ipsum dolor sit amet, consectetur adipiscing elit.

但无论出于何种原因(包含元素的宽度设置,使用文本缩放等),在查看器的屏幕上它显示为两行或更多行.

Lorem ipsum dolor sit amet,

consectetur adipiscing elit.

要么

Lorem ipsum dolor sit

amet, consectetur

adipiscing elit.

有没有办法通过javascript找出那些换行发生的地方？

$('p').text()并$('p').html()返回,Lorem ipsum dolor sit amet, consectetur adipiscing elit.无论文本如何显示.

Answer 1

好吧,如果你想要一些非常简单的东西,可能对你来说太无用了(如果你在段落中有任何类型的HTML,它将需要进行重大修改),那么看看这个:

var para = $('p');

para.each(function(){
    var current = $(this);
    var text = current.text();
    var words = text.split(' ');

    current.text(words[0]);
    var height = current.height();

    for(var i = 1; i < words.length; i++){
        current.text(current.text() + ' ' + words[i]);

        if(current.height() > height){
            height = current.height();
            // (i-1) is the index of the word before the text wraps
            console.log(words[i-1]);
        }
    }
});

这太简单了,它可能会起作用.这样做是通过空格分解文本,然后逐字追加单词,观察元素高度的任何增加,这表示换行.

看看这里:http://www.jsfiddle.net/xRPYN/2/

Answer 2

对于像pdf生成这样的用例.

您可以限制每行的字符数,如果分割出现中间字,则进行适当调整.

要获得每行更准确的字符,可以使用等宽字体,然后确定允许的每种字体的每个字符的宽度.然后将字符宽度除以允许的文本行宽度的大小,并且您将拥有该字体的每行允许的字符数.

你可以使用非等宽字体,但是你必须测量每个字母的宽度 - 呃.一种可以自动进行宽度猜测的方法是使用没有边距或填充的跨度,为每个字体(和大小)添加每个字符,然后测量跨度的宽度并使用它.

我已经完成了代码:

/**
 * jQuery getFontSizeCharObject
 * @version 1.0.0
 * @date September 18, 2010
 * @since 1.0.0, September 18, 2010
 * @package jquery-sparkle {@link http://www.balupton/projects/jquery-sparkle}
 * @author Benjamin "balupton" Lupton {@link http://www.balupton.com}
 * @copyright (c) 2010 Benjamin Arthur Lupton {@link http://www.balupton.com}
 * @license Attribution-ShareAlike 2.5 Generic {@link http://creativecommons.org/licenses/by-sa/2.5/
 */
$.getFontSizeCharObject = function(fonts,sizes,chars){
    var fonts = fonts||['Arial','Times'],
        sizes = sizes||['12px','14px'],
        chars = chars||['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','y','x','z',
                        'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','Y','X','Z',
                        '0','1','2','3','4','5','6','7','8','9','-','=',
                        '!','@','#','$','%','^','&','*','(',')','_','+',
                        '[',']','{','}','\\','|',
                        ';',"'",':','"',
                        ',','.','/','<','>','?',' '],
        font_size_char = {},
        $body = $('body'),
        $span = $('<span style="padding:0;margin:0;letter-spacing:0:word-spacing:0"/>').appendTo($body);

    $.each(fonts, function(i,font){
        $span.css('font-family', font);
        font_size_char[font] = font_size_char[font]||{};
        $.each(sizes, function(i,size){
            $span.css('font-size',size);
            font_size_char[font][size] = font_size_char[font][size]||{};
            $.each(chars,function(i,char){
                if ( char === ' ' ) {
                    $span.html('&nbsp;');
                }
                else {
                    $span.text(char);
                }
                var width = $span.width()||0;
                font_size_char[font][size][char] = width;
            });
        });
    });

    $span.remove();

    return font_size_char;
};

/**
 * jQuery adjustedText Element Function
 * @version 1.0.0
 * @date September 18, 2010
 * @since 1.0.0, September 18, 2010
 * @package jquery-sparkle {@link http://www.balupton/projects/jquery-sparkle}
 * @author Benjamin "balupton" Lupton {@link http://www.balupton.com}
 * @copyright (c) 2010 Benjamin Arthur Lupton {@link http://www.balupton.com}
 * @license Attribution-ShareAlike 2.5 Generic {@link http://creativecommons.org/licenses/by-sa/2.5/
 */
$.fn.adjustedText = function(text,maxLineWidth){
    var $this = $(this),
        font_size_char = $.getFontSizeCharObject(),
        char_width = font_size_char['Times']['14px'],
        maxLineWidth = parseInt(maxLineWidth,10),
        newlinesAt = [],
        lineWidth = 0,
        lastSpace = null;

    text = text.replace(/\s+/g, ' ');

    $.each(text,function(i,char){
        var width = char_width[char]||0;
        lineWidth += width;
        if ( /^[\-\s]$/.test(char) ) {
            lastSpace = i;
        }
        //console.log(i,char,lineWidth,width);
        if ( lineWidth >= maxLineWidth ) {
            newlinesAt.push(lastSpace||i);
            lineWidth = width;
            lastSpace = null;
        }
    });

    $.each(newlinesAt,function(i,at){
        text = text.substring(0,at+i)+"\n"+text.substring(at+i);
    });

    text = text.replace(/\ ?\n\ ?/g, "\n");

    console.log(text,newlinesAt);

    $this.text(text);

    return $this;
};

$(function(){
    var $body = $('body'),
        $textarea = $('#mytext'),
        $btn = $('#mybtn'),
        $div = $('#mydiv');

    if ( $textarea.length === 0 && $div.length === 0 ) {
        $body.empty();

        $textarea = $('<textarea id="mytext"/>').val('(When spoken repeatedly, often three times in succession: blah blah blah!) Imitative of idle, meaningless talk; used sometimes in a slightly derogatory manner to mock or downplay another\'s words, or to show disinterest in a diatribe, rant, instructions, unsolicited advice, parenting, etc. Also used when recalling and retelling another\'s words, as a substitute for the portions of the speech deemed irrelevant.').appendTo($body);
        $div = $('<div id="mydiv"/>').appendTo($body);
        $btn = $('<button id="mybtn">Update Div</button>').click(function(){
            $div.adjustedText($textarea.val(),'300px');
        }).appendTo($body);

        $div.add($textarea).css({
            'width':'300px',
            'font-family': 'Times',
            'font-size': '14px'
        });
        $div.css({
            'width':'auto',
            'white-space':'pre',
            'text-align':'left'
        });
    }

});

Answer 3

这就是我最终使用的内容(随意批评并复制以用于您自己的邪恶目的).

首先,当编辑从用户进入时,它就被打破了$(editableElement).lineText(userInput).

jQuery.fn.lineText = function (userInput) {
   var a = userInput.replace(/\n/g, " \n<br/> ").split(" ");
   $.each(a, function(i, val) { 
      if(!val.match(/\n/) && val!="") a[i] = '<span class="word-measure">' + val + '</span>';
   });
   $(this).html(a.join(" "));
};

换行更换是因为编辑文本框已填充$(editableElement).text(),忽略<br/>标记,但它们仍将更改显示中以下行的高度以进行排版.这不是最初目标的一部分,只是相当低调的成果.

当我需要提取格式化文本时,我打电话$(editableElement).getLines(),在哪里

jQuery.fn.getLines = function (){
   var count = $(this).children(".word-measure").length;
   var lineAcc = [$(this).children(".word-measure:eq(0)").text()];
   var textAcc = [];
   for(var i=1; i<count; i++){
      var prevY = $(this).children(".word-measure:eq("+(i-1)+")").offset().top;
      if($(this).children(".word-measure:eq("+i+")").offset().top==prevY){
         lineAcc.push($(this).children(".word-measure:eq("+i+")").text());
   } else {
     textAcc.push({text: lineAcc.join(" "), top: prevY});
     lineAcc = [$(this).children(".word-measure:eq("+i+")").text()];
   }
   }
   textAcc.push({text: lineAcc.join(" "), top: $(this).children(".word-measure:last").offset().top});
   return textAcc;
};

最终结果是哈希列表,每个哈希包含单行文本的内容和垂直偏移.

[{"text":"Some dummy set to","top":363},
 {"text":"demonstrate...","top":382},
 {"text":"The output of this","top":420},
 {"text":"wrap-detector.","top":439}]

如果我只想要无格式文本,$(editableElement).text()仍然会返回

"Some dummy set to demonstrate... The output of this wrap-detector."

Answer 4

一旦你有一个更复杂的结构,如段落中的链接(例如,你可以<b><i><a href></a>在一个内<p>),上面的解决方案不起作用.

所以我创建了一个javascript库来检测在这些情况下换行的位置:http://github.com/xdamman/js-line-wrap-detector

我希望这有帮助.