判断图片格式的代码(判断jpg,png,gif,tiff)

load = function(path){ 
  //var fullpath = ..io.exist(path)
  //if( fullpath ) return dll.ImageLoadW(owner.hImage,fullpath); 

  var buffer = ..string.loadBuffer(path);  
  if( buffer ){
    if( buffer[1] == 0xFF &&  buffer[2] == 0xD8 ){
      path="*.jpg"
    }
    elseif( buffer[1] == 0x89 &&  buffer[2] == 0x50 &&  buffer[3] == 0x4e &&  buffer[4] == 0x47){
      path="*.png"
    } 
    elseif( buffer[1] == 0x47 &&  buffer[2] == 0x49 &&  buffer[3] == 0x46){
      path="*.gif"
    }
    elseif( buffer[1] == 0x0C &&  buffer[2] == 0xED){
      path="*.tiff"
    }
    return dll.ImageFromStringB(owner.hImage,buffer,#buffer,path);
  }
}

代码原理是根据图片的头文件格式进行判断,要知道每种图片格式都有自己特定的头文字格式.