uweb/searchurl/textarea.js
2021-09-06 13:54:12 +08:00

83 lines
2.5 KiB
JavaScript

var textarea;
onload=function(){
textarea=document.getElementsByTagName('textarea')[0];
}
function getNewlinePos_back(text,pos){
while(pos>=0 && text.charAt(pos)!='\n') pos--;
return pos;
}
function getNewlinePos_forth(text,pos){
let len = text.length;
while(pos<len && text.charAt(pos)!='\n') pos++;
return pos;
}
function deleteLine(ta){
let text = ta.value;
let lStart = getNewlinePos_back(text,ta.selectionStart-1);
let lEnd = getNewlinePos_forth(text,ta.selectionEnd);
ta.value = text.substring(0,lStart+1) + text.substring(lEnd+1);
ta.selectionStart = ta.selectionEnd = lStart +1;
ta.focus();
}
function moveUp(ta){
let text = ta.value;
let start = ta.selectionStart;
let end = ta.selectionEnd;
let lStart = getNewlinePos_back(text,start-1);
let lEnd = getNewlinePos_forth(text,end);
let prevS = getNewlinePos_back(text,lStart-1);
ta.value = text.substring(0,prevS+1)+text.substring(lStart+1,lEnd+1)+
text.substring(prevS+1,lStart+1) + text.substring(lEnd+1);
ta.selectionStart = start - (lStart - prevS);
ta.selectionEnd = end - (lStart - prevS);
ta.focus();
}
function move2Top(ta){
let text = ta.value;
let start = ta.selectionStart;
let end = ta.selectionEnd;
let lStart = getNewlinePos_back(text,start-1);
let lEnd = getNewlinePos_forth(text,end);
ta.value = text.substring(lStart+1,lEnd+1)+text.substring(0,lStart+1)+
text.substring(lEnd+1);
ta.selectionStart = start - lStart-1;
ta.selectionEnd = end - lStart-1;
ta.focus();
}
function move2Bottom(ta){
let text = ta.value;
let start = ta.selectionStart;
let end = ta.selectionEnd;
let lStart = getNewlinePos_back(text,start-1);
let lEnd = getNewlinePos_forth(text,end);
ta.value = text.substring(0,lStart+1)+text.substring(lEnd+1)+
text.substring(lStart+1,lEnd+1);
ta.selectionStart = start + text.length - lEnd-1;
ta.selectionEnd = end + text.length - lEnd-1;
ta.focus();
}
function moveDown(ta){
let text = ta.value;
let start = ta.selectionStart;
let end = ta.selectionEnd;
let lStart = getNewlinePos_back(text,start-1);
let lEnd = getNewlinePos_forth(text,end);
let nextE = getNewlinePos_forth(text,lEnd+1);
ta.value = text.substring(0,lStart+1) + text.substring(lEnd+1,nextE+1) +
text.substring(lStart+1,lEnd+1)+text.substring(nextE+1);
ta.selectionStart = start + (nextE - lEnd);
ta.selectionEnd = end + (nextE - lEnd);
ta.focus();
}
function onSave(fn){
let u8=new TextEncoder().encode(textarea.value);let r='';for(let i=0;i<u8.byteLength;i++)r+=String.fromCharCode(u8[i]);location.href='i:0l'+fn+':'+btoa(r);
}