Regex 如何从文件创建jpg URL列表？

我想从读取的文件创建扩展名为.jpg的url列表。例如，包含html源代码的文件

在本例中，我使用来自的html源代码

我试着

grep 'http:\/\/[\da-z0-9\.\/\-]*\.jpg' index.html

但结果是

<meta property="og:image" content="http://static.hdw.eweb4.com/media/thumbs/1/137/1360695.jpg" />
<meta name="twitter:image:src" content="http://static.hdw.eweb4.com/media/thumbs/1/137/1360695.jpg" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360695.jpg" width="192" height="120" alt="Valentine&#039;s Day, Girl, Carnation" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360683.jpg" width="192" height="108" alt="Waterfall, Water, Moss, Rock" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360717.jpg" width="192" height="108" alt="Wing, Lexus, Neon" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360750.jpg" width="192" height="108" alt="Field, Planet, Sky, Cloud, Moon, Tree, Water" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360688.jpg" width="192" height="120" alt="Eye, Brunette" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360685.jpg" width="192" height="108" alt="Forest, Tree, Fog, Path" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1363741.jpg" width="192" height="108" alt="Curve, Line" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360682.jpg" width="192" height="108" alt="desktop, wallpapers, cool, city, paris, backgrounds, widescreen, definition, high, wallpaper" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360677.jpg" width="192" height="108" alt="Eagle, Bird, Neon" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360673.jpg" width="192" height="108" alt="Apple, Mac, Macintosh, Windows" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360705.jpg" width="192" height="108" alt="Brunette" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360681.jpg" width="192" height="108" alt="Superman, DC Comics" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1363584.jpg" width="192" height="120" alt="Water, Drop" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360639.jpg" width="192" height="120" alt="Tom Clancy&#039;s Ghost Recon, Tom Clancy, Ghost Recon" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360775.jpg" width="192" height="108" alt="Skull, Gun, Pistol" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360634.jpg" width="192" height="120" alt="wallpaper, blue, cool, background, images" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/139/1382198.jpg" width="192" height="108" alt="River, Rock, Summer" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361319.jpg" width="192" height="120" alt="Mansion, Plane, Bench, Wood, Path, Sky, Cloud, Tree" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1364274.jpg" width="192" height="108" alt="wallpaper, nature, widescreen, background, images" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361077.jpg" width="192" height="108" alt="Lion, Nebula, Fire" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361129.jpg" width="192" height="120" alt="wallpaper, cool" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361057.jpg" width="192" height="108" alt="Sphere" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1367677.jpg" width="192" height="120" alt="Tiger" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/139/1381054.jpg" width="192" height="120" alt="Peacock, Bird" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1360872.jpg" width="192" height="108" alt="Summer, Tree, Sky, Sun" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1364275.jpg" width="192" height="108" alt="wallpapers, couple, images, backgrounds, wallpaper" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361440.jpg" width="192" height="120" alt="Apple, Mac, Macintosh" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361247.jpg" width="192" height="108" alt="colorful, wallpaper, mac, world, wallpapers, cool" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361149.jpg" width="192" height="108" alt="cool, pools, houses, wallpaper, widescreen, house, swimming" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1364182.jpg" width="192" height="108" alt="landscape, background, mountain, wallpaper, widescreen, images" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/139/1382183.jpg" width="192" height="120" alt="Church, Snow, Winter, Sky, Mountain" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/139/1381058.jpg" width="192" height="108" alt="Floral, Butterfly" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1332346.jpg" width="192" height="120" alt="Lion, Lioness" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1362750.jpg" width="192" height="120" alt="Bimota Tesi 3D, Bimota" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/133/1329810.jpg" width="192" height="108" alt="Water, Tree, Rock, Sky" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/133/1327308.jpg" width="192" height="120" alt="Pebble" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1365181.jpg" width="192" height="120" alt="Blossom, Spring, Tree, Park, Path" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/138/1377008.jpg" width="192" height="120" alt="Summer, Sky, Cloud, Tree" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1330430.jpg" width="192" height="120" alt="Love, Heart" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/133/1327256.jpg" width="192" height="120" alt="Rose" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/136/1352316.jpg" width="192" height="108" alt="Water, Ocean, Sky, Tree, Resort, Pool" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/138/1378312.jpg" width="192" height="120" alt="Puppy, Dog, Labrador Retriever" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1365033.jpg" width="192" height="108" alt="Railroad, Lake" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1332674.jpg" width="192" height="108" alt="Mouse, Headphone" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1330463.jpg" width="192" height="120" alt="Curve" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/135/1346818.jpg" width="192" height="120" alt="Brunette, Woman" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1362808.jpg" width="192" height="108" alt="Butterfly, Sparkle" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/138/1377438.jpg" width="192" height="120" alt="White Tiger, Tiger" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/136/1352316.jpg" width="192" height="108" alt="Water, Ocean, Sky, Tree, Resort, Pool" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/133/1327137.jpg" width="192" height="120" alt="Forget-me-not" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/138/1377515.jpg" width="192" height="108" alt="Selena Gomez" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1337525.jpg" width="192" height="108" alt="happy, wallpaper, wallpapers, funny" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/136/1353933.jpg" width="192" height="120" alt="White Tiger, Tiger" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/135/1348007.jpg" width="192" height="120" alt="Valentine&#039;s Day, Love, Heart" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/133/1327551.jpg" width="192" height="120" alt="Winter, Snow, Sun, Field, Grass, Tree, Sky, Cloud" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1332067.jpg" width="192" height="120" alt="Daffodil, Chicken, Chick" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1361583.jpg" width="192" height="108" alt="Forest, Tree" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/133/1327514.jpg" width="192" height="120" alt="Sunset, Bench, Lake, Sky" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/137/1362750.jpg" width="192" height="120" alt="Bimota Tesi 3D, Bimota" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/135/1348183.jpg" width="192" height="120" alt="Lion" border="0" style="margin:0px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/132/1312950.jpg" width="192" height="108" alt="At the Devil&#039;s Door" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1331552.jpg" width="192" height="108" alt="Unicorn" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/134/1333430.jpg" width="192" height="108" alt="Lada" border="0" style="margin:6px 0;" />
    <img src="http://static.hdw.eweb4.com/media/thumbs/1/138/1377141.jpg" width="192" height="108" alt="Explosion" border="0" style="margin:6px 0;" />

只需打印URL即可。

查看grep命令的“-o”（-仅匹配）选项。

---

默认情况下，grep保留与给定模式匹配的行。使用选项'-o'，grep将只保留与您的url模式匹配的部分行

您尝试了什么？你被困在哪里？您的文件示例是什么样子的？请阅读并回答您的问题，以包含这些详细信息。刚刚编辑，请重新审阅。