收集小技巧

shell列出目录树形结构

#安装tree
brew install tree
#使用tree命令
tree
#深层结构
tree -L 2

python 初始化数组

res = ["" for _ in range(10)]
res[0]="abc"

python svg转png/ico

import cairosvg
import io
from PIL import Image

def svg_to_png(svg_content, output_path, width=None, height=None):
    """
    将SVG代码转换为PNG图片
    
    Args:
        svg_content: SVG代码字符串
        output_path: 输出PNG文件路径
        width: 可选，输出图片宽度
        height: 可选，输出图片高度
    """
    # 将SVG转换为PNG
    if width and height:
        png_data = cairosvg.svg2png(bytestring=svg_content.encode('utf-8'), 
                                   output_width=width, 
                                   output_height=height)
    else:
        png_data = cairosvg.svg2png(bytestring=svg_content.encode('utf-8'))
    
    # 保存PNG文件
    with open(output_path, 'wb') as png_file:
        png_file.write(png_data)
        
def png_to_ico(png_path, ico_path, sizes=None, optimize=True):
    """
    将PNG图片转换为ICO图标
    
    Args:
        png_path: PNG文件路径
        ico_path: 输出ICO文件路径
        sizes: 图标尺寸列表，默认为常用尺寸
        optimize: 是否优化图像质量
    """
    if sizes is None:
        sizes = [16, 24, 32, 48, 64, 128, 256]  # 常用ICO尺寸
    
    try:
        # 打开原始PNG图像
        original_img = Image.open(png_path)
        
        # 确保图像模式为RGBA（支持透明度）
        if original_img.mode != 'RGBA':
            original_img = original_img.convert('RGBA')
        
        images = []
        
        for size in sizes:
            try:
                # 调整图像尺寸，保持宽高比
                img_resized = original_img.resize(
                    (size, size), 
                    Image.Resampling.LANCZOS  # 高质量重采样
                )
                images.append(img_resized)
                
            except Exception as e:
                print(f"Warning: Failed to resize to {size}x{size}: {e}")
                continue
        
        if not images:
            raise ValueError("No valid icons were generated")
        
        # 保存为ICO文件（包含所有尺寸）
        images[0].save(
            ico_path,
            format='ICO',
            sizes=[(img.width, img.height) for img in images],
            append_images=images[1:] if len(images) > 1 else None
        )
        
        return True
        
    except Exception as e:
        print(f"Error converting PNG to ICO: {e}")
        return False