Hướng dẫn html select option set selected value php - html select option đặt giá trị đã chọn php

Tóm tắt: Trong hướng dẫn này, bạn sẽ tìm hiểu cách sử dụng phần tử

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

Giới thiệu nhanh về yếu tố

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue

  

Code language: HTML, XML [xml]

Phần tử

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

• /**
   * Private helper function for checked, selected, disabled and readonly.
   *
   * Compares the first two arguments and if identical marks as $type
   *
   * @since 2.8.0
   * @access private
   *
   * @param mixed  $helper  One of the values to compare
   * @param mixed  $current [true] The other value to compare if not just true
   * @param bool   $echo    Whether to echo or just return the string
   * @param string $type    The type of checked|selected|disabled|readonly we are doing
   * @return string html attribute or empty string
   */
  function __checked_selected_helper[ $helper, $current, $echo, $type ] {
      if [ [string] $helper === [string] $current ] {
          $result = " $type='$type'";
      } else {
          $result = '';
      }
  
      if [ $echo ] {
          echo $result;
      }
  
      return $result;
  }
  

  2 -

  /**
   * Private helper function for checked, selected, disabled and readonly.
   *
   * Compares the first two arguments and if identical marks as $type
   *
   * @since 2.8.0
   * @access private
   *
   * @param mixed  $helper  One of the values to compare
   * @param mixed  $current [true] The other value to compare if not just true
   * @param bool   $echo    Whether to echo or just return the string
   * @param string $type    The type of checked|selected|disabled|readonly we are doing
   * @return string html attribute or empty string
   */
  function __checked_selected_helper[ $helper, $current, $echo, $type ] {
      if [ [string] $helper === [string] $current ] {
          $result = " $type='$type'";
      } else {
          $result = '';
      }
  
      if [ $echo ] {
          echo $result;
      }
  
      return $result;
  }
  

  2 liên kết phần tử

  /**
   * Outputs the html selected attribute.
   *
   * Compares the first two arguments and if identical marks as selected
   *
   * @since 1.0.0
   *
   * @param mixed $selected One of the values to compare
   * @param mixed $current  [true] The other value to compare if not just true
   * @param bool  $echo     Whether to echo or just return the string
   * @return string html attribute or empty string
   */
  function selected[ $selected, $current = true, $echo = true ] {
      return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
  }
  

  7 với phần tử

  /**
   * Private helper function for checked, selected, disabled and readonly.
   *
   * Compares the first two arguments and if identical marks as $type
   *
   * @since 2.8.0
   * @access private
   *
   * @param mixed  $helper  One of the values to compare
   * @param mixed  $current [true] The other value to compare if not just true
   * @param bool   $echo    Whether to echo or just return the string
   * @param string $type    The type of checked|selected|disabled|readonly we are doing
   * @return string html attribute or empty string
   */
  function __checked_selected_helper[ $helper, $current, $echo, $type ] {
      if [ [string] $helper === [string] $current ] {
          $result = " $type='$type'";
      } else {
          $result = '';
      }
  
      if [ $echo ] {
          echo $result;
      }
  
      return $result;
  }
  

  5

• /**
   * Private helper function for checked, selected, disabled and readonly.
   *
   * Compares the first two arguments and if identical marks as $type
   *
   * @since 2.8.0
   * @access private
   *
   * @param mixed  $helper  One of the values to compare
   * @param mixed  $current [true] The other value to compare if not just true
   * @param bool   $echo    Whether to echo or just return the string
   * @param string $type    The type of checked|selected|disabled|readonly we are doing
   * @return string html attribute or empty string
   */
  function __checked_selected_helper[ $helper, $current, $echo, $type ] {
      if [ [string] $helper === [string] $current ] {
          $result = " $type='$type'";
      } else {
          $result = '';
      }
  
      if [ $echo ] {
          echo $result;
      }
  
      return $result;
  }
  

  6 - Thuộc tính

  /**
   * Private helper function for checked, selected, disabled and readonly.
   *
   * Compares the first two arguments and if identical marks as $type
   *
   * @since 2.8.0
   * @access private
   *
   * @param mixed  $helper  One of the values to compare
   * @param mixed  $current [true] The other value to compare if not just true
   * @param bool   $echo    Whether to echo or just return the string
   * @param string $type    The type of checked|selected|disabled|readonly we are doing
   * @return string html attribute or empty string
   */
  function __checked_selected_helper[ $helper, $current, $echo, $type ] {
      if [ [string] $helper === [string] $current ] {
          $result = " $type='$type'";
      } else {
          $result = '';
      }
  
      if [ $echo ] {
          echo $result;
      }
  
      return $result;
  }
  

  6 liên kết với giá trị cho một bản gửi biểu mẫu.

Phần tử

/**
 * Private helper function for checked, selected, disabled and readonly.
 *
 * Compares the first two arguments and if identical marks as $type
 *
 * @since 2.8.0
 * @access private
 *
 * @param mixed  $helper  One of the values to compare
 * @param mixed  $current [true] The other value to compare if not just true
 * @param bool   $echo    Whether to echo or just return the string
 * @param string $type    The type of checked|selected|disabled|readonly we are doing
 * @return string html attribute or empty string
 */
function __checked_selected_helper[ $helper, $current, $echo, $type ] {
    if [ [string] $helper === [string] $current ] {
        $result = " $type='$type'";
    } else {
        $result = '';
    }

    if [ $echo ] {
        echo $result;
    }

    return $result;
}

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

Nếu một tùy chọn không có thuộc tính

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

/**
 * Private helper function for checked, selected, disabled and readonly.
 *
 * Compares the first two arguments and if identical marks as $type
 *
 * @since 2.8.0
 * @access private
 *
 * @param mixed  $helper  One of the values to compare
 * @param mixed  $current [true] The other value to compare if not just true
 * @param bool   $echo    Whether to echo or just return the string
 * @param string $type    The type of checked|selected|disabled|readonly we are doing
 * @return string html attribute or empty string
 */
function __checked_selected_helper[ $helper, $current, $echo, $type ] {
    if [ [string] $helper === [string] $current ] {
        $result = " $type='$type'";
    } else {
        $result = '';
    }

    if [ $echo ] {
        echo $result;
    }

    return $result;
}

Để chọn tùy chọn khi trang tải lần đầu tiên, bạn có thể thêm thuộc tính

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

/**
 * Private helper function for checked, selected, disabled and readonly.
 *
 * Compares the first two arguments and if identical marks as $type
 *
 * @since 2.8.0
 * @access private
 *
 * @param mixed  $helper  One of the values to compare
 * @param mixed  $current [true] The other value to compare if not just true
 * @param bool   $echo    Whether to echo or just return the string
 * @param string $type    The type of checked|selected|disabled|readonly we are doing
 * @return string html attribute or empty string
 */
function __checked_selected_helper[ $helper, $current, $echo, $type ] {
    if [ [string] $helper === [string] $current ] {
        $result = " $type='$type'";
    } else {
        $result = '';
    }

    if [ $echo ] {
        echo $result;
    }

    return $result;
}

Ví dụ sau chọn tùy chọn

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

Background Color:

	--- Choose a color ---
	Red
	Green
	Blue
Code language: HTML, XML [xml]

Nhận giá trị đã chọn từ một phần tử

Chúng tôi sẽ tạo một biểu mẫu sử dụng phần tử

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}

Đầu tiên, hãy tạo các thư mục và tệp sau:

├── css
|  └── style.css
├── inc
|  ├── footer.php
|  ├── get.php
|  ├── header.php
|  └── post.php
└── index.php
Code language: JavaScript [javascript]

Thứ hai, đặt mã sau vào tệp tiêu đề.php:

    
    
    
    PHP select option



    
Code language: HTML, XML [xml]

Thứ ba, đặt mã sau vào tệp footer.php:

Code language: HTML, XML [xml]

Thứ tư, thêm mã sau vào tệp get.php để tạo biểu mẫu có một phần tử

/**
 * Outputs the html selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare
 * @param mixed $current  [true] The other value to compare if not just true
 * @param bool  $echo     Whether to echo or just return the string
 * @return string html attribute or empty string
 */
function selected[ $selected, $current = true, $echo = true ] {
    return __checked_selected_helper[ $selected, $current, $echo, 'selected' ];
}