php中几个字符函数小结
  下面小结PHP中的几个字符函数，小结一下：

1）ucfirst
   将首字母变大写，比如
  $string = "this is my web development blog";

echo ucfirst($string);

// Output: This is my web development blog

2) lcfirst,将首字母变小写
   $string = "This is my Web Development Blog";

echo lcfirst($string);

// Output: this is my Web Development Blog

3）strtoupper,将整个字符串变大写
   $string = "this is my web development blog";

echo strtoupper($string);

// Output: THIS IS MY WEB DEVELOPMENT BLOG

4） strtoplower，将整个字符串变小写
   $string = "tHiS is mY WeB DevElOpMenT bLoG";

echo strtolower($string);

// Output: this is my web development blog

5）ucwords(),可以将句子中每个单词的第一个字母变大写，比如
   $string = "this is my web development blog";

echo ucwords($string);

// Output: This Is My Web Development Blog