我应该创建一个PHP应用程序，让用户计算他们为达到投资目标而需要投入的金额。
有两种投资选择：
在我提供的HTML模板中，有两个单选按钮可决定选择哪个投资选项。根据检查的是哪一个，为每个实施一个公式。
公式通过提取月度利率，未来投资目标和时间（月数）来计算所需投资金额三个文本框。问题是，当我点击提交按钮时，我会继续获得值＆＃34; 0＆＃34;。
<form action="<?php $_SERVER['PHP_SELF']?>" method="POST">
<fieldset>
<legend id="Investment Strategy">Investment Strategy:</legend>
<input type="radio" name="investmentStrategy" value="lumpsum" />Lump sum Investment ($)
<br />
<input type="radio" name="investmentStrategy" value="monthly" />Monthly Investment ($)
<br />
</fieldset>
<br />
<fieldset>
<legend id="Investment Goal">Investment Goal:</legend>
<p>
<label>Desired future amount ($):</label>
<input type="text" name="futureamount" value="" />
</p>
<p>
<label>Investment term/period (years):</label>
<input type="text" name="term" value="" />
</p>
<p>
<label>Desired rate of return/interest (%/year):</label>
<input type="text" name="interest" value="" />
</p>
</fieldset>
<p>
<input type="reset" name="reset" value="Reset" />
<input type="submit" name="submit" value="Calculate Amount to Invest" />
</p>
</form>
<br />
<?php
$investmentValue = 0;
$investmentTerm = 0;
$investmentInterest = 0;
$monthlyInvestment = 0;
$lumpsumInvestment = 0;
$interestRate = 0;
$futureValue = 0;
$num_of_months = 0;
// Define functions and implement formula
function ComputeMonthlyPayment($interestRate, $futureValue, $num_of_months){
$monthlyInvestment = ($interestRate * $futureValue) / (pow(1+$interestRate, $num_of_months)-1);
return $monthlyInvestment;
}
function ComputeLumpsumPayment($interestRate, $futureValue, $num_of_months){
$lumpsumInvestment = ($interestRate * $futureValue) / (pow(1+$interestRate, $num_of_months));
return $lumpsumInvestment;
}
if(isset ($_POST['submit'])){
$radio_value = $_POST['investmentStrategy'];
if((isset($radio_value) && $radio_value=="lumpsum")){
// Extract inputs and call function
$investmentValue = @$_POST['futureamount'];
$investmentTerm = @$_POST['term'];
$investmentInterest = @$_POST['interest'];
// Call function
ComputeLumpsumPayment($investmentInterest, $investmentValue, $investmentTerm);
// Display function
echo $lumpsumInvestment;
} elseif((isset($radio_value) && $radio_value == "monthly")) {
$investmentValue = @$_POST['futureamount'];
$investmentTerm = @$_POST['term'];
$investmentInterest = @$_POST['interest'];
// Call function
ComputeMonthlyPayment($investmentInterest, $investmentValue, $investmentTerm);
// Display investment
echo $monthlyInvestment;
}
} else {
echo $test;
}
?>
答案 0 :(得分：0)
无线电值应视为数组。我对您的代码进行了一些小修改：
$ radio_value应该是一个数组，所以我使用$ radio_value [0]获取第一个索引，因为你只是获得每月或者lumpsum，并在输入类型元素上返回该值，以便用户知道他/她在选择什么。
使用函数时，应将调用函数放入变量中，以便在需要时调用变量，使用的变量与函数无关。
<强> PHP
// Define functions and implement formula
function ComputeMonthlyPayment($interestRate, $futureValue, $num_of_months){
$monthlyInvestment = ($interestRate * $futureValue) / (pow(1+$interestRate, $num_of_months)-1);
return $monthlyInvestment;
}
function ComputeLumpsumPayment($interestRate, $futureValue, $num_of_months){
$lumpsumInvestment = ($interestRate * $futureValue) / (pow(1+$interestRate, $num_of_months));
return $lumpsumInvestment;
}
if(isset ($_POST['submit'])){
if(isset($_POST['investmentStrategy'])) {
$radio_value = $_POST['investmentStrategy'];
$futureamount = $_POST['futureamount'];
$term = $_POST['term'];
$interest = $_POST['interest'];
}
if((isset($radio_value[0]) && $radio_value[0] =="lumpsum")){
// Extract inputs and call function
$investmentValue = $futureamount;
$investmentTerm = $term;
$investmentInterest = $interest;
// Call function
$lumpsumInvestment = ComputeLumpsumPayment($investmentInterest, $investmentValue, $investmentTerm);
// Display function
echo $lumpsumInvestment;
} elseif((isset($radio_value[0]) && $radio_value[0] == "monthly")) {
$investmentValue = $futureamount;
$investmentTerm = $term;
$investmentInterest = $interest;
// Call function
$monthlyInvestment = ComputeMonthlyPayment($investmentInterest, $investmentValue, $investmentTerm);
// Display investment
echo $monthlyInvestment;
}
} else {
echo $test;
}
?>
<强> HTML
<form action="<?php echo $_SERVER['PHP_SELF']?>" method="POST">
<fieldset>
<legend id="Investment Strategy">Investment Strategy:</legend>
<input type="radio" name="investmentStrategy[]" value="lumpsum" <?php echo $radio_value[0] == "lumpsum" ? "CHECKED" : ""; ?> />Lump sum Investment ($)
<br />
<input type="radio" name="investmentStrategy[]" value="monthly" <?php echo $radio_value[0] == "monthly" ? "CHECKED" : ""; ?> />Monthly Investment ($)
<br />
</fieldset>
<br />
<fieldset>
<legend id="Investment Goal">Investment Goal:</legend>
<p>
<label>Desired future amount ($):</label>
<input type="text" name="futureamount" value="<?php echo $futureamount; ?>" />
</p>
<p>
<label>Investment term/period (years):</label>
<input type="text" name="term" value="<?php echo $term; ?>" />
</p>
<p>
<label>Desired rate of return/interest (%/year):</label>
<input type="text" name="interest" value="<?php echo $interest; ?>" />
</p>
<强> PS：
我没有触及你的计算方式。 ^ _ ^