mirror of https://github.com/jkjoy/sunpeiwen.git
66 lines
1.4 KiB
JavaScript
66 lines
1.4 KiB
JavaScript
'use strict'
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var stringWidth = require('string-width')
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exports.center = alignCenter
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exports.left = alignLeft
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exports.right = alignRight
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// lodash's way of generating pad characters.
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function createPadding (width) {
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var result = ''
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var string = ' '
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var n = width
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do {
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if (n % 2) {
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result += string;
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}
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n = Math.floor(n / 2);
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string += string;
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} while (n);
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return result;
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}
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function alignLeft (str, width) {
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var trimmed = str.trimRight()
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if (trimmed.length === 0 && str.length >= width) return str
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var padding = ''
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var strWidth = stringWidth(trimmed)
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if (strWidth < width) {
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padding = createPadding(width - strWidth)
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}
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return trimmed + padding
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}
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function alignRight (str, width) {
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var trimmed = str.trimLeft()
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if (trimmed.length === 0 && str.length >= width) return str
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var padding = ''
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var strWidth = stringWidth(trimmed)
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if (strWidth < width) {
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padding = createPadding(width - strWidth)
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}
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return padding + trimmed
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}
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function alignCenter (str, width) {
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var trimmed = str.trim()
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if (trimmed.length === 0 && str.length >= width) return str
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var padLeft = ''
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var padRight = ''
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var strWidth = stringWidth(trimmed)
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if (strWidth < width) {
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var padLeftBy = parseInt((width - strWidth) / 2, 10)
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padLeft = createPadding(padLeftBy)
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padRight = createPadding(width - (strWidth + padLeftBy))
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}
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return padLeft + trimmed + padRight
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}
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