function FindDllInPath(const DllName, SearchPath: string): string;
| DllName | string |
| SearchPath | string |
stringFindDllInPath combines SearchPath and DllName and returns the full path when that file exists
It is the single-directory probe used by the higher-level PDFium DLL search helpers
DllPath := FindDllInPath('pdfium.dll', GetApplicationPath);