Add image information retrieval method and test

2 files changed, 30 insertions, 0 deletions

diff --git a/fpdf.go b/fpdf.go
index c7042c7..470a81b 100644
--- a/fpdf.go
+++ b/fpdf.go
@@ -2358,6 +2358,18 @@ func (f *Fpdf) RegisterImage(fileStr, tp string) (info *ImageInfoType) {
 	return f.RegisterImageReader(fileStr, tp, file)
 }
 
+// GetImageInfo returns information about the registered image specified by
+// imageStr. If the image has not been registered, an empty structure followed
+// by false is returned. The internal error is not modified by this method.
+func (f *Fpdf) GetImageInfo(imageStr string) (info ImageInfoType, ok bool) {
+	var infoPtr *ImageInfoType
+	infoPtr, ok = f.images[imageStr]
+	if ok {
+		info = *infoPtr
+	}
+	return
+}
+
 // GetXY returns the abscissa and ordinate of the current position.
 //
 // Note: the value returned for the abscissa will be affected by the current
diff --git a/fpdf_test.go b/fpdf_test.go
index 81ff68f..b556713 100644
--- a/fpdf_test.go
+++ b/fpdf_test.go
@@ -1083,9 +1083,27 @@ func ExampleFpdf_RegisterImage() {
 		pdf.Image(imageFileStr, lf, tp, imgWd, imgHt, false, "", 0, "")
 	}
 	fileStr := exampleFilename("Fpdf_RegisterImage")
+	// Test the image information retrieval method
+	infoShow := func(imageStr string) {
+		imageStr = imageFile(imageStr)
+		info, ok := pdf.GetImageInfo(imageStr)
+		if ok {
+			if info.Width() > 0.0 {
+				fmt.Printf("Image %s is registered\n", imageStr)
+			} else {
+				fmt.Printf("Incorrect information for image %s\n", imageStr)
+			}
+		} else {
+			fmt.Printf("Image %s is not registered\n", imageStr)
+		}
+	}
+	infoShow(fileList[0])
+	infoShow("foo.png")
 	err := pdf.OutputFileAndClose(fileStr)
 	summary(err, fileStr)
 	// Output:
+	// Image image/logo-gray.png is registered
+	// Image image/foo.png is not registered
 	// Successfully generated pdf/Fpdf_RegisterImage.pdf
 }