The name 'CheckExtension' does not exist in the current contextCheckExtension不是C#自带的函数么?

the name the first name名 the family name姓 the last the given name名the first name the family name the last name the given name the background of name Name of the dinosaur_____size______food______. in the name of Name the main character take the name take the name Whats the( )name? Remember the name keep the name是什么意思 Remember the name歌词 name the data nad the given name是什么意思 rember the name 歌词 the name of... the first name和given name和full name和middle name是什么意思 In China,the last name is the g_v_n name.