简体中文(ZH-CN) English(EN) 繁体中文(ZH-TW) 日本語(JA) 한국어(KO) Melayu(MS) Français(FR) Deutsch(DE)
Home > Backend Development > PHP Tutorial > body text

php filter_has_var determines whether a variable exists function_PHP tutorial

WBOY
Release： 2016-07-20 11:00:31
Original
1108 people have browsed it

​

Definition and usage
The filter_has_var() function checks if a variable of the specified input type exists.

Returns TRUE or FALSE on success on failure.

Grammar

filter_has_var(type, variable)
Copy after login
Copy after login
Copy after login
Copy after login










	

	
	
	type
Copy after login

			
	
	
    
	
  • 
	必需的。指定类型检查可能存在的输入类型：
	INPUT_GET
    • 
	
  • INPUT_POST
    • 
	
  • INPUT_COOKIE
    • 
	
  • INPUT_SERVER
    • 
	
  • INPUT_ENV
    • 
	

			
	

	

	variable
	
	必需的。指定变量检查
	
	







    

  • 
Required. Specify type checking for possible input types:
INPUT_GET
    • 

  • INPUT_POST
    • 

  • INPUT_COOKIE
    • 

  • INPUT_SERVER
    • 

  • INPUT_ENV
    • 







variable

Required. Specify variable check







Copy after login
Copy after login
Copy after login



例如
在这个例子中的输入变量“名称”发送到PHP页面：
Copy after login



Copy after login
Copy after login
Copy after login


<!--?phpif(!filter_has_var(INPUT_GET, "name")) { echo("Input type does not exist"); }else { echo("Input type exists"); }?-->
Copy after login


输出为.
Copy after login


 Input type exists
Copy after login









www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/445506.htmlTechArticleDefinition and Usage The filter_has_var() function checks if a variable of the specified input type exists. Returns TRUE or FALSE on success on failure. Syntax filter_has_var(type, variable)...



                

            

            

                                

                    Related labels：
                    

                        filter has php var function judgment variable exist usage                    

                

                                
source：php.cn

                            

            

                                    
                        Previous article：Getting Started with PHP: strrchr Example Tutorial_PHP Tutorial
                    
                                    
                        Next article：PHP function strcmp function example tutorial_PHP tutorial
                    
                            

            

       
                
Statement of this Website

                
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

            

           

            

                
Latest Articles by Author

                
            

            

                
Latest Issues

                

                                        

                        

                            PHP arrays obtained from URL parameters do not behave as expected
                            I have a URL parameter that contains the category ID and I want to treat it as an array li...
                            

                                

                                     From 2024-04-06 22:09:02
                                

                                

                                    
  0 

                                    
1

                                    
1428

                                

                            

                        

                    

                    

                                        

                        

                            Where should I place CustomLog directive in apache
                            I'm using php:7.2-apachedocker. I need to disable health check url login access log. Based...
                            

                                

                                     From 2024-04-06 22:03:59
                                

                                

                                    
  0 

                                    
1

                                    
990

                                

                            

                        

                    

                    

                                        

                        

                            What is the format of the variables in the return value?
                            I am a new learner of php. I found a piece of code: if($x<time()){return[false,'error']...
                            

                                

                                     From 2024-04-06 21:55:20
                                

                                

                                    
  0 

                                    
1

                                    
778

                                

                            

                        

                    

                    

                                        

                        

                            Problems encountered when using opentbs to generate odt files: values ​​of the same key are displayed in the same row instead of separate columns.
                            I'm using a library called OpenTbs to create odt using PHP, I'm using it because columns a...
                            

                                

                                     From 2024-04-06 20:18:18
                                

                                

                                    
  0 

                                    
1

                                    
483

                                

                            

                        

                    

                    

                                        

                        

                            Group MySQL results by ID for looping over
                            I have a table with flight data in mysql. I'm writing a php code that will group and displ...
                            

                                

                                     From 2024-04-06 17:27:56
                                

                                

                                    
  0 

                                    
1

                                    
406

                                

                            

                        

                    

                    

                                    

            

            

                

                    
Related Topics

                    More>
                    
                

                

                    
                

            

        

    

    

        

            
Popular Recommendations

            

                
            

        

        
        

            

                
Popular Tutorials

                More>
                
            

            

                

                    
Related Tutorials 

                    
Popular Recommendations

                    
Latest courses

                

                
                
                
            

            
        


        

            

                
Latest Downloads

                More>
                
            

                        
            

                

                    
Web Effects 

                    
Website Source Code

                    
Website Materials

                    
Front End Template

                

                
                
                
                
            

            
        

    





    

        

            

                

                    

                        About us
                        Disclaimer
                        Sitemap
                        

                    

                    
php.cn：Public welfare online PHP training，Help PHP learners grow quickly！