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Question

I have been trying for hours to use PowerShell (and numerous StackOverflow threads/Google articles) - but failed to make this work.

I have this PowerShell Script:

$URI = "http://example.html"
$HTML = Invoke-WebRequest -Uri $URI

Which returns the HTML below. I am just trying to get the "In" and "Out" values which appears under "Average max 5 min values for Daily' Graph (5 Minute interval): - and not the weekly' values, which have almost identical tags.

<!-- End Head -->
<!-- Begin `Daily' Graph (5 Minute --><div class="graph">
        <h2>`Daily' Graph (5 Minute Average)</h2>
        <img src="aklsr2_gi0_1-day.png" title="day" alt="day" />
        <table>
            <tr>
                <th></th>
                <th scope="col">Max</th>
                <th scope="col">Average</th>
                <th scope="col">Current</th>
            </tr>
            <tr class="in">
                <th scope="row">In</th>
                <td>9939.4 kb/s (99.4%)</td>
                <td>1908.7 kb/s (19.1%) </td>
                <td>80.8 kb/s (0.8%) </td>
            </tr>
            <tr class="out">
                <th scope="row">Out</th>
                <td>9682.3 kb/s (96.8%) </td>
                <td>344.1 kb/s (3.4%) </td>
                <td>83.8 kb/s (0.8%) </td>
            </tr>
            <tr>
                <td colspan="8">
                    Average max 5 min values for `Daily' Graph (5 Minute interval):
                    <span class="in">In</span> 2264.1 kb/s (22.6%)/
                    <span class="out">Out</span> 451.0 kb/s (4.5%)
                </td>
            </tr>
        </table>
    </div>
<!-- End `Daily' Graph (5 Minute -->

<!-- Begin `Weekly' Graph (30 Minute -->
    <div class="graph">
        <h2>`Weekly' Graph (30 Minute Average)</h2>
        <img src="aklsr2_gi0_1-week.png" title="week" alt="week" />
        <table>
            <tr>
                <th></th>
                <th scope="col">Max</th>
                <th scope="col">Average</th>
                <th scope="col">Current</th>
            </tr>
            <tr class="in">
                <th scope="row">In</th>
                <td>9939.4 kb/s (99.4%)</td>
                <td>1273.3 kb/s (12.7%) </td>
                <td>98.8 kb/s (1.0%) </td>
            </tr>
            <tr class="out">
                <th scope="row">Out</th>
                <td>9775.1 kb/s (97.8%) </td>
                <td>249.9 kb/s (2.5%) </td>
                <td>61.6 kb/s (0.6%) </td>
            </tr>
            <tr>
                <td colspan="8">
                    Average max 5 min values for `Weekly' Graph (30 Minute interval):
                    <span class="in">In</span> 2236.6 kb/s (22.4%)/
                    <span class="out">Out</span> 593.8 kb/s (5.9%)
                </td>
            </tr>
        </table>
    </div>
<!-- End `Weekly' Graph (30 Minute -->

Answer 1

You can use the -match comparison operator. -match will match only the first occurrence, and since the values are the first ones in the HTML output, it will give you the values you need. You can do something like this:

$regexes = @('<span class="in">In<\/span> (.*)/', '<span class="out">Out</span> (.*)')

$regexes | ForEach-Object {
    $htmlText -match $_ 
    $Matches[1]
}