Bash Shell代码不响应while、loop、date

为了测试它，我对while循环进行了注释，但是我的shell脚本有一些地方出了问题

name = ""
while [test -z name]; do
echo "Please enter your name:"
read name
done
echo "Hello $name"
echo $date
hour = $(date +H)
if test $hour -ge 9
then
echo "Welcome you are on time again!"
else
echo "You are running behind your scheduled time!"
echo "Employees must be logged in by 9 am."
echo "$name arrived late on $date" >> checkin
fi

未注释while时，它不会进入循环。我想这与我的条件反射有关。它也不能正确地输入if语句。我不确定这是什么正确的格式

输出如下所示：

project2: line 1: name: command not found
project2: line 2: [test: command not found
Hello 

project2: line 8: hour: command not found
project2: line 9: [test: command not found
You are running behind your scheduled time!
Employees must be logged in by 9 am.

编辑2：我不知道这是否合法，但它是这样的：

while循环已修复，谢谢各位。你知道我的if陈述是怎么回事吗

新代码：

name = ""
while test -z "$name"
do
   echo "Please enter your name:"
   read name
done
echo "Hello $name"
echo $date
hour = $(date +H)
if test "$hour" -ge "9"
then
  echo "Welcome you are on time again!"
else
  echo "You are running behind your scheduled time!"
  echo "Employees must be logged in by 9 am."
  echo "$name arrived late on $date" >> checkin
fi

输出

Please enter your name:

Please enter your name:

Please enter your name:
Jack
Hello Jack

project2: line 9: hour: command not found
project2: line 10: test: : integer expression expected
You are running behind your scheduled time!
Employees must be logged in by 9 am.

请输入您的姓名，根据代码和输入重复正确。你知道if语句是怎么回事吗？这就是bash shell，我可能应该提到。

这是您的代码的修订版，它充分利用了bash的功能-所有更改都用注释标记：

  # NO spaces allowed around `=` in ASSIGNMENTS.
  # Note: By contrast, when `=` or `==` are used 
  #       in CONDITIONALS for COMPARISON, you MUST have spaces around them.
name=""
  # Use `[[ ... ]]` rather than `[ ... ]` or `test` in bash":
  # It's more robust (mostly no need for quoting) and
  # has more features.
  # You MUST have a space after `[[` and before `]]` (same goes for `[` and `]`).
while [[ -z $name ]]
do
   echo "Please enter your name:"
   read name
done
echo "Hello, $name"
  # There is no `$date` variable. But you can use 
  # COMMAND SUBSTITUTION - `$(...)` to capture the
  # `date` utility's output:
dateNow=$(date)
  # NO spaces around `=`; `H` must be prefixed with `%`
  # to return the hour (thanks, @alvits).
hour=$(date +%H)
  # Use ARITHMETIC EVALUATION - `(( ... ))`
  # for numerical comparisons.
  # You can refer to variables without the $ prefix,
  # and use C-style arithmetic expressions.
if (( hour > 9 ))
then
  echo "Welcome, you are on time again!"
else
  echo "You are running behind your scheduled time!"
  echo "Employees must be logged in by 9 am."
  echo "$name arrived late on $dateNow" >> checkin
fi

下面是代码的修订版，它充分利用了bash的功能—所有更改都用注释标记：

  # NO spaces allowed around `=` in ASSIGNMENTS.
  # Note: By contrast, when `=` or `==` are used 
  #       in CONDITIONALS for COMPARISON, you MUST have spaces around them.
name=""
  # Use `[[ ... ]]` rather than `[ ... ]` or `test` in bash":
  # It's more robust (mostly no need for quoting) and
  # has more features.
  # You MUST have a space after `[[` and before `]]` (same goes for `[` and `]`).
while [[ -z $name ]]
do
   echo "Please enter your name:"
   read name
done
echo "Hello, $name"
  # There is no `$date` variable. But you can use 
  # COMMAND SUBSTITUTION - `$(...)` to capture the
  # `date` utility's output:
dateNow=$(date)
  # NO spaces around `=`; `H` must be prefixed with `%`
  # to return the hour (thanks, @alvits).
hour=$(date +%H)
  # Use ARITHMETIC EVALUATION - `(( ... ))`
  # for numerical comparisons.
  # You can refer to variables without the $ prefix,
  # and use C-style arithmetic expressions.
if (( hour > 9 ))
then
  echo "Welcome, you are on time again!"
else
  echo "You are running behind your scheduled time!"
  echo "Employees must be logged in by 9 am."
  echo "$name arrived late on $dateNow" >> checkin
fi

---

变量赋值不应在=”周围包含空格

使用[…]的语句必须在开括号后有空格，在闭括号前有空格

变量的前缀必须为$。而[-z$name]应该足以测试name是否为空

您应该从hour=$date+H更改为hour=$date+%H，以实际分配小时值，而不是字母H

---

echo$date引用名为date的变量。但是您没有名为date的变量，因此它将打印为空。

变量赋值不应在=”周围包含空格

使用[…]的语句必须在开括号后有空格，在闭括号前有空格

变量的前缀必须为$。而[-z$name]应该足以测试name是否为空

您应该从hour=$date+H更改为hour=$date+%H，以实际分配小时值，而不是字母H

---

echo$date引用名为date的变量。但是您没有名为date的变量，因此它将打印为空。

变量赋值不应在=”周围包含空格。使用[…]的语句必须在开括号后有空格，在闭括号前有空格。变量的前缀必须为$。while[-z$name]应该足以测试名称是否为空。谢谢，修复了while循环。你知道if语句是怎么回事吗？应该是if[$hour-ge 9]。它不起作用，因为$hour的值是H。你应该改为hour=$date+%H。echo$date引用了一个名为date的变量。但是您没有名为date的变量，因此它将打印为空。变量赋值不应在=（日期）周围包含空格。使用[…]的语句必须在开括号后有空格，在闭括号前有空格。变量的前缀必须为$。while[-z$name]应该足以测试名称是否为空。谢谢，修复了while循环。你知道if语句是怎么回事吗？应该是if[$hour-ge 9]。它不起作用，因为$hour的值是H。你应该改为hour=$date+%H。echo$date引用了一个名为date的变量。但您没有名为date的变量，因此它将打印为空。@YohanesKhosiawan许先汉: 谢谢你这么说。这是一个伟大的分解所有问题与上述代码在一个奇妙的格式。谢谢你。@JFA：我的荣幸；我很高兴你觉得它很有用。@YohanesKhosiawan许先汉: 谢谢你这么说。这是一个伟大的分解所有问题与上述代码在一个奇妙的格式。谢谢你。@JFA：我的荣幸；我很高兴你觉得它很有用。