笙默考试管理系统-MyExamTest----codemirror（39）
目录
一、 笙默考试管理系统-MyExamTest
二、 笙默考试管理系统-MyExamTest
三、 笙默考试管理系统-MyExamTest
四、 笙默考试管理系统-MyExamTest
五、 笙默考试管理系统-MyExamTest
return chunk.lines[n];
}
function lineNo(line) {
if (line.parent == null) return null;
var cur = line.parent, no = indexOf(cur.lines, line);
for (var chunk = cur.parent; chunk; cur = chunk, chunk = chunk.parent) {
for (var i = 0, e = chunk.children.length; ; ++i) {
if (chunk.children[i] == cur) break;
no += chunk.children[i].chunkSize();
}
}
return no;
}
function lineAtHeight(chunk, h) {
var n = 0;
outer: do {
for (var i = 0, e = chunk.children.length; i < e; ++i) {
var child = chunk.children[i], ch = child.height;
if (h < ch) { chunk = child; continue outer; }
h -= ch;
n += child.chunkSize();
}
return n;
} while (!chunk.lines);
for (var i = 0, e = chunk.lines.length; i < e; ++i) {
var line = chunk.lines[i], lh = line.height;
if (h < lh) break;
h -= lh;
}
return n + i;
}
function heightAtLine(chunk, n) {
var h = 0;
outer: do {
for (var i = 0, e = chunk.children.length; i < e; ++i) {
var child = chunk.children[i], sz = child.chunkSize();
if (n < sz) { chunk = child; continue outer; }
n -= sz;
h += child.height;
}
return h;
} while (!chunk.lines);
for (var i = 0; i < n; ++i) h += chunk.lines[i].height;
return h;
}
// The history object 'chunks' changes that are made close together
// and at almost the same time into bigger undoable units.
function History() {
this.time = 0;
this.done = []; this.undone = [];
}
History.prototype = {
addChange: function(start, added, old) {
this.undone.length = 0;
var time = +new Date, last = this.done[this.done.length - 1];
if (time - this.time > 400 || !last ||
last.start > start + added || last.start + last.added < start - last.added + last.old.length)
this.done.push({start: start, added: added, old: old});
else {
var oldoff = 0;
if (start < last.start) {
for (var i = last.start - start - 1; i >= 0; --i)
last.old.unshift(old[i]);
last.added += last.start - start;
last.start = start;
}
else if (last.start < start) {
oldoff = start - last.start;
added += oldoff;
}
for (var i = last.added - oldoff, e = old.length; i < e; ++i)
last.old.push(old[i]);
if (last.added < added) last.added = added;
}
this.time = time;
}
};
