Inserting Images Dynamically
You can insert images to your reports dynamically using image
tags. To declare a dynamically inserted image within your template, do the following steps:
- Add a textbox to your template at the place where you want an image to be inserted.
- Set common image attributes such as frame, size, and others for the textbox, making the textbox look like a blank inserted image.
- Specify an
image
tag within the textbox using the following syntax.
<<image [image_expression]>>
The expression declared within an image
tag is used by the engine to build an image to be inserted. The expression must return a value of one of the following types:
- A byte array containing an image data
- A Stream instance able to read an image data
- An Image object
- A string containing an image URI, path, or Base64-encoded image data
While building a report, the following procedure is applied to an image
tag:
- The expression declared within the tag is evaluated and its result is used to form an image.
- The corresponding textbox is filled with this image.
- The tag is removed from the textbox.
Note – If the expression declared within an image
tag returns a stream object, then it is closed by the engine as soon as the corresponding image is built.
By default, the engine stretches an image filling a textbox to the size of the textbox without preserving the ratio of the image. However, you can change this behavior in the following ways:
- To keep the size of the textbox and stretch the image within bounds of the textbox preserving the ratio of the image, use the
keepRatio
switch as follows.<<image [image_expression] -keepRatio>>
- To keep the width of the textbox and change its height according to the ratio of the image, use the
fitHeight
switch as follows.<<image [image_expression] -fitHeight>>
- To keep the height of the textbox and change its width according to the ratio of the image, use the
fitWidth
switch as follows.<<image [image_expression] -fitWidth>>
- To change the size of the textbox according to the size of the image, use the
fitSize
switch as follows.<<image [image_expression] -fitSize>>
- To change the size of the textbox according to the size of the image without increasing the size of the textbox, use the
fitSizeLim
switch as follows.<<image [image_expression] -fitSizeLim>>
Note – If the size of the image is greater than the size of the textbox, then the fitSizeLim
switch acts like fitHeight
or fitWidth
. Otherwise, the fitSizeLim
switch acts like fitSize
.