ant-design-vue/components/input-number/src/hooks/useCursor.ts

79 lines
2.1 KiB
TypeScript

import { warning } from '../../../vc-util/warning';
import type { Ref } from 'vue';
import { ref } from 'vue';
/**
* Keep input cursor in the correct position if possible.
* Is this necessary since we have `formatter` which may mass the content?
*/
export default function useCursor(
inputRef: Ref<HTMLInputElement>,
focused: Ref<boolean>,
): [() => void, () => void] {
const selectionRef = ref<{
start?: number;
end?: number;
value?: string;
beforeTxt?: string;
afterTxt?: string;
}>(null);
function recordCursor() {
// Record position
try {
const { selectionStart: start, selectionEnd: end, value } = inputRef.value;
const beforeTxt = value.substring(0, start);
const afterTxt = value.substring(end);
selectionRef.value = {
start,
end,
value,
beforeTxt,
afterTxt,
};
} catch (e) {
// Fix error in Chrome:
// Failed to read the 'selectionStart' property from 'HTMLInputElement'
// http://stackoverflow.com/q/21177489/3040605
}
}
/**
* Restore logic:
* 1. back string same
* 2. start string same
*/
function restoreCursor() {
if (inputRef.value && selectionRef.value && focused.value) {
try {
const { value } = inputRef.value;
const { beforeTxt, afterTxt, start } = selectionRef.value;
let startPos = value.length;
if (value.endsWith(afterTxt)) {
startPos = value.length - selectionRef.value.afterTxt.length;
} else if (value.startsWith(beforeTxt)) {
startPos = beforeTxt.length;
} else {
const beforeLastChar = beforeTxt[start - 1];
const newIndex = value.indexOf(beforeLastChar, start - 1);
if (newIndex !== -1) {
startPos = newIndex + 1;
}
}
inputRef.value.setSelectionRange(startPos, startPos);
} catch (e) {
warning(
false,
`Something warning of cursor restore. Please fire issue about this: ${e.message}`,
);
}
}
}
return [recordCursor, restoreCursor];
}