使用javascript在textarea中选择之前和之后插入文本

Question

How to insert text before and after selection in textarea with javascript? Selection occurs into a textarea field of a HTML form

Answer 1

Simple script that works in both IE, MFF and GC where myField is a object reference. Assembled by several scripts found through the web.

function insertAtCursor(myField, myValueBefore, myValueAfter) {

    if (document.selection) {

        myField.focus();
        document.selection.createRange().text = myValueBefore + document.selection.createRange().text + myValueAfter;


    } else if (myField.selectionStart || myField.selectionStart == '0') {

        var startPos = myField.selectionStart;
        var endPos = myField.selectionEnd;
        myField.value = myField.value.substring(0, startPos)+ myValueBefore+ myField.value.substring(startPos, endPos)+ myValueAfter+ myField.value.substring(endPos, myField.value.length);

    } 
}

Answer 2

Try the following:

var selectionText = yourTextarea.value.substr(yourTextarea.selectionStart, yourTextarea.selectionEnd);
yourTextarea.value = "Text before" + selectionText + "Text after";

If you want to search + replace then the following code will do the trick (In non IE browsers)

var textBeforeSelection = yourTextarea.value.substr(0, yourTextarea.selectionStart);
var textAfterSelection = yourTextarea.value.substr(yourTextarea.selectionEnd, yourTextarea.value.length);
yourTextarea.value = textBeforeSelection + " new selection text " + textAfterSelection;