引导程序将选择与按钮和两个输入字段对齐

只需使用此代码代替您的代码即可。.在引导程序中，有一个名为Col-lg-n，col-md-n。的类。这会将屏幕划分为n列。最大n值为12。代码

<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12" >
<div class="container">
    <div class="row">
        <form method="POST" action="reportGenerator.php" class="form-inline">
            <div class="input-group">
                <div class="col-lg-3 col-md-3">
                    <input type="text" id="From" class="form-control" name="From" placeholder="Date From">
                </div>
                <div  class="col-lg-3 col-md-3">
                    <input type="text" id="To" class="form-control" name="To" placeholder="Date To">
                </div>
                <div class="col-lg-3 col-md-3">
                    <select name="Target" class="form-control" type="button" id="Target" data-toggle="dropdown">
                        <OPTION>Sale</OPTION>
                        <OPTION>Purchase</OPTION>
                    </select>
                </div>

                <div class="col-lg-3 col-md-3">
                    <span class="input-group-btn">
                        <input class="btn btn-default" type="submit" value="Generate Report" />
                    </span>
                </div>

            </div>
        </form>
    </div>
</div>