I'm making a file edit interface in my web-app, I have a textarea with file contents.
When textarea is focused, I want to output the position of the cursor, i.e. line number and column: this is useful because error messages usually yield a line number, for example.
The question is: how do I figure out the position of the cursor in textarea? I'm using prototype library. Maybe there's a solution already?
I'm not really interested in fancy toolbars for the textarea, which are offered by those advanced widgets.
You may want to check out these 2 links:
http://www.dedestruct.com/2008/03/22/howto-cross-browser-cursor-position-in-textareas/[The orginal source does not exist any more, the modified link points to the latest version of the Web Archive]
https://developer.mozilla.org/En/DOM:Selection
..once you have a selection (cursor index in text), you can split your text by newlines, thus getting line number. you can get column by determining index from beginning of a line
When I want the current line number of textarea and current column of textarea, I solved like this:
<textarea onkeyup="getLineNumberAndColumnIndex(this);" onmouseup="this.onkeyup();" > </textarea> function getLineNumberAndColumnIndex(textarea){ var textLines = textarea.value.substr(0, textarea.selectionStart).split("\n"); var currentLineNumber = textLines.length; var currentColumnIndex = textLines[textLines.length-1].length; console.log("Current Line Number "+ currentLineNumber+" Current Column Index "+currentColumnIndex ); }
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